wimax calculations
DESCRIPTION
Calculations utilized in WiMAX. WiMAX is a technology that aimed at providing high BW services to a userTRANSCRIPT
WIRELESS BROADBAND NETWORK
WIMAX AND 3G
Showing newest 22 of 62 posts from 02/01/2008 - 03/01/2008. Show older posts
Showing newest 22 of 62 posts from 02/01/2008 - 03/01/2008. Show older posts
W I M A X T R A N S M I T P O W E R C A L C U L A T I O N
Do we need to consider return loss of the device along with insertion loss
when we calculate the output power of the particular device?
For example Balun has return loss of 12dB and IL of 2.5 dB, when i give input
to the balun as 0dBm what will be the out put of the balun power available?
output power= Input power-IL or
output power= Input power-(IL+RL)?
In such case if the input to the BALUN is 0dBm then the output of the Balun
will be -15dBm because of the return loss 12 dB and insertion loss 2.6dB, Is
this calculation correct?
If there is really a 12 dB return loss in the balun then the calculation is
correct.
Iam just wondering why the RL of the Balun is 12dB. I think it is quite large.
We use balun to match impedance and minimize RL.
Can you tell how the value of RL obtained?
Do not consider the return loss when making your link budget or EIRP
calculations. The insersion loss is to be considered (only).
The return loss is the indicator of the health of your cable and antenna
together. The antenna is an impedence matching device from the cable (50
ohms) to free space (377 ohms) and is frequency dependant.
Since there is no perfect impedence match there will be some reflected
power. A return loss of 13 db means that 1/20 th of the power was reflected.
If you were transmitting 10 watts than .5 watts was refected. This number is
too little to worry about.
However, if you see reflected power start to rise you must ceck your cable
and antenna and jumpers.
i over looked return loss as loss due to return instead of loss of the return.
thats why i think its value is high for a loss.
to consider it theoretically in your calculation. just subtract the linear value
of RL form 1 then convert it back to dB
for 12dB RL means 1/16 of incident is reflected hence 15/16 is for the load
(1-1/16)
So your loss due to return is 10log(15/16)= - 0.28dB
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I M P O R T A N C E O F T H E T R A N S M I T T I G A N T E N N A G A I N F O R T H E
B A S E S T A T I O N
As per my RF design i am getting +40dBm Tx power at the antenna port
after subctracting the insertion loss and Returm loss of Balun and TDD
switch, the same Power(+40dBm)is fed to TX directional antenna, My
Question is ,Will the TX Antenna gain(G) would help to increase radiated
power more than 42dBm?
Please help me in understanding more on the inportance of antenna
Gain(G)?
Forward power consists of transmit power minus cable and connector loss,
minus combiner loss (if applicable) plus atnenna gain (in dbi) = EIRP
Example: 20 Watts = +43 dbm - 3 db cable loss = +40 dbm, plus 15 dbi of
antenna gain = +55 dbm EIRP
http://www.satcom.co.uk/article.asp?article=21
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W I M A X R E C E I V E R S E N S I T I V I T Y
I have some problem to understand the Sensitivity Calcutaion in IEEE
802.16e-2005.
For the OFDM PHY, at page 351 of the standard (Receiver Requirements), the
sensitivity is scaled by the number of active subchannel (for example in
downlink i can use only one among 16 channels).
In the OFDMA part (page 646, Receiver sensitivity) in the expression appear
Nused*(Fs/Nfft), where I understand that Nused are all subcarrier except DC
subcarrier.
So, there is a difference in the calculation. For the OFDMA the expression
rapresent the minimum received power that guaranted a BER of 10^-6, in
the case of the end user in uplink used all the available channels.
This is the worse case, infact the subcanalization has the following
advantage:
1) the trasmitter power is concentrated in a limited bandwidth, so this can
increase the coverage
2) the Bandwith, in the expression of sensitivity, is smaller, so the minimum
received power is less that in the case of all sub-channel allocated to one
user.
Can anyone explain me the difference?
Receiver sensitivity is a factor of bandwidth as follows:
Receiver sensitivity = -174 + 10log BW + NF of receive amp
so, the narrower the bandwidth the lower the noise, hense the lower the
receive thereshold for narrower BW.
The Standard 802.16e (I refer to OFDMA) specify:
Rss=-114+ SNRrx - 10log(Repetition Factor) + 10log( FS x Nused / Nfft) +
ImpLoss + NF
Where, in according to the definition of "Nused", the term "Fs x Nused / Nfft"
is practicaly the bandwidth occupied by all sub-channels.
So, this is the minimum sensitivity for a user that use all available
subchannels (in OFDMA). But if a MS use only one subchannel, the BW is
narrow hense the receive thereshold is lower.
If I use this expression for sensitivity calculation I have the worst case
results, because the expression don't take in account the effect of
subchanalization.
Is this true?
Maybe, I think I can take in account the canalizazion effect as a Gain in the
link budget (One gain for the power concentration in a sub-channel, and one
gain to compensate the fact that the sensitivity, in reality, is better).
But my problem is: "how can I foreseen the canalization gain if I don't know
how many sub-channels the scheduler of the BS allocate for each user?"
Download the 802.16e standard (if you haven't already) and do a "find" on
the key words "Link Budget". You will find your answers here.
I started to try to describe Link Budgets and Path Balance but they do a
better job than I do.
"Receiver sensitivity = -174 + 10log BW + NF of receive amp"
What's NF? Is this equation valid for single carrier modulation?
-174 is the thermal noise floor, 10log BW applies to bandwidths, run a couple
of exercises, try 200 khz, then 1.25 Mhz then 5 Mhz, etc.
NF is the noise figure of the receive amp. BTS amps run around 5-7 db,
smaller cellphone amps run higher.
Receiver threshold is the amount of receive signal required to obtain a
certain throughput at 1 x 10-6
What about this equation Rss= SNR-10log(BW/Rb) + Nw +Nf
Nw:thermal noise floor ; Rb: data rate (b/s)
is it equivalent, there is an extra term (SNR+logRb).
An other question: the required SNR have to be calculated or is given, what's
the formula if yes?
The signal part of the equation depends on the strength of the recieve signal.
The noise part is dependent of the bandwidth of the receive filter. The next
factor to understand is the interference, because the determining factor for
throughput will be decide by the type of modulation and coding, and that is
determined by the Signal to Noise + Interference sometimes written CINR for
Carrier to Interference & Noise Ratio or C/N+I.
I was referred to this equation just to have relation between the range and
the throughput, actually I forgot the source.
Also I’m working with the following formula:
Rss=-174+10 log(BW(Hz))+SNR+NF+10log(Nsubchannels)
Referring to an example of BL attached. Also I use these values of SNR:
Modulation coding rate SNR Rx
BPSK ½ 6.4
QPSK ½ 9.4
QPSK ¾ 11.2
16-QAM ½ 16.4
16-QAM ¾ 18.2
64-QAM 2/3 22.7
64-QAM ¾ 24.4
Are those values valid for all bandwidths (exactly 25MHz)?
Other question, what are the typical values of antenna gain? directive=17
dBi; omnidirectionnel=0 dBi what about sectoriel?
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M O D U L A T I O N
Dear Friends,
Can any one share the info about the ideal values of CINR and RSSI vaule at
different bandwidth and modulation.
Bandwith : 3 , 3.5 ,6 6.5 MHz
Modulation :
BPSK ½
QPSK ½
QPSK ¾
QAM 16 ½
QAM 16 ¾
QAM 64 2/3
QAM 64 ¾
please note that the values differ from vendor to fendor.
The following table referes to a 3.5MHz BW System:
Typical levels for BER <1x10-6 are given.
Modulation / FEC / Rx Sensitivity / CINR
64QAM 3/4 -80.0dBm 23.0dB
64QAM 2/3 -82.0dBm 21.0dB
16QAM 3/4 -86.0dBm 17.0dB
16QAM 1/2 -88.0dBm 15.0dB
QPSK 3/4 -92.0dBm 11.0dB
QPSK 1/2 -94.0dBm 9.0dB
BPSK 1/2 -98.0dBm 5.0dB
these values are for BER <1x10 E-6, and they tend to produce a packet loss
of about 1x10 E-2 which is fine for TCP, but a murder for UDP/RTP
multimedia.
Also, consider faster scheduling types in case multimedia is a key role of
your network. Check for performance with short packets - ther may be some
surprises with latencies and throughput ;)
This information is provided by the vendor. The vendor will provide a
minimum signal strength to achieve each modulation/coding scheme.
The noisie floor is dependant of the bandwidth (-174 + 10logBW/hz) plus the
Noise Figure of the receive amplifier. The NF will vary by vendor and will also
vary if set at the top of the tower (close to the antenna) or on the ground
(typically in the base station).
Frequency reuse will increase the signal strength requirement (S/N+I)
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F R E Q U E N C Y P L A N N I N G
Which is the best plan for frequency reuse in wimax. Moreover how
important is the synchronization of BTS.
What kind of equipments -BST do u use TDD or FDD?
"Synchronized TDD"
As PMP networks are built out and carriers obtain a larger mass of
customers, channels within each
base station will need to be reused for maximum capacity to serve a growing
customer base. Once the
same frequency begins to be reused in a given base station (or FR greater
than 1), additional complexities
for RF planning must be considered. Although both TDD and FDD suffer
greater interference issues in
this more built-out network, the unique pattern for TDD of base station- base
station interference
becomes much more acute. The solution is to implement intrahub and
interhub synchronization.
In addition, with TDD, no guard bands are required to separate upstream and
downstream frequency
traffic. Usually as much as 200 to 300 MHz frequency separation is needed
between transmit and receive
frequencies for cost-effective modem designs in FDD.
I would suggest a BS with 4 sectors, each 90 deg. (180deg. antennas are
expensive and difficult to obtain).
What do you meen with "different polarity" - I assume you meen polarization.
Is that right?
I also added a pic to explain the frequency reuse plan.
Regards
Harald
Attachments
FrequencyPlan.JPG, 37 KB
Thanks Harald, yes u are right I mean polarization. by 180 degree i meant that i use four sector, let say Sect A, B , C and D. Sect A and C (that are 180 apart from each other) will use the same frequency but one horizental and other vertical and sect B and D will use diff pair of frequency with same arrangement.
Are you not concerned about working with different polarizations in the same network on one BTS? I think for mobile you should stick to vertical polarization. What planning tool are you using? CINR statistics will be needed to analyze your network performance, deploying this frequency plan.
I have the same doubts like Aleks about separating sectors only by polarization:Imagine if sector A and sector C are transmitting on the same frequency (even with different polarization) the antenna in sector A with its finit front-to-back ratio will fire also into sector C. This will effect CINR in sector C. The same will happen also on sector A.
Typical values for a 90deg antenna are:gain: 15.5dBihor plane: 90degver plane: 6.7degfront ot back ratio: 25dB
CINR will be affected considerably, taking into account these typical values.I have one question a little out if this discussion, but it may be useful. What are the typical values of which I can put between the adjacent frequencies as described in the screenshot? Also, how can I calculate the separation in dB needed between the adjacent carrier frequencies?
I will need it when I input the frequency plan in order to get a correct CINR analysis.
Thank you in advance for your time and consideration.
Kind regards,
Aleks
Attachments
carriers.JPG, 41 KB
depending on the modulation, bandwidth, FEC and required BER you need the following SNR: please see uploaded pic SNR.jpgThe table gives you an overview how modulation, bandwidth, FEC and minimum receive level are related. Data are derived from Source: WiMAX ForumConformance Testing to IEEE Std 802.16-2004—Part 3: Radio Conformance Tests (RCT) for WirelessMAN-OFDM™ and WirelessHUMAN (OFDM)™ Air Interface
Now it is up to you to provide this SNR!Check your transmit spectrum and then deside how far you have to separate your carrier frequencies.
Kind regardsHarald
Attachments
SNR.JPG, 71 KB
RX-Selecitivity.JPG, 42 KB
in the Specification Data Sheet from a WiMAX Vendor I found that the attenuation fromchannel n to channel n+1 (the adjucent channel) is 31dB, and fromchannel n to channel n+2 is 50dB.
Well, in all mobile networks I have seen vertical polarization is used. This is based on the specifics of radio propagation in this frequency band and antennas. As you know the propagation method for frequencies above 1800
MHz is reflection, not diffraction. I can send you a document, describing the reasons for what I am saying.
Also, mixing polarization typed in one network is not adviseable, according to my understanding and what I have been taught in university and training courses. And I am pretty sure that vertical polarization is well enough for a mobile network.
Actually, there is no need for a certain polarisation in areas potentially covered with mobile WiMAX, as there is no notable difference in propagation for such small cell footprints. Also, you can't expect any mobile device to operate with only one polarisation. To tackle it, you have various diversity schemes, so called x-polarisation being the most popular in mobile networks. With MIMO, and somewhat elaborated antennas, it is all dealt with in a convenient way,and you don't have to worry about it ;)
the amount of bandwidth you need depends on you services.What type of services have you planned?Depending on your type of service for example, latency varies from vendor to vendor within the same configuration significantly.Our round trip delay measurement results areVendor A: min. 28ms, max. 45ms (useful for VoIP)Vendor B: min. 146ms, max. 509ms (not useful for VoIP, caused by high delay and jitter)So you have to find out if you can live with it or not.
ATPC:Automatic Transmit Power Contrrol (ATPC) is a feature that allows the system to self-optimize the transmit power and provide for the best overall link performance. The ATPC function automatically will adjust the output power level of remote-end systems to match a pre-specified signal strength value.
When ATPC is enabled, the system will attempt to establish the wireless link and exchange performance information. Once the wireless link is established, the master-end system will dynamically adjust the remote-end systems transmit power to maintain optimum link characteristics while minimizing power output. In short, ATPC optimizes the transmission power for best operation, while minimizing excess power and interference with other devices.
Practical examples:Vendor X: BS adjustable from +13dBm to +28dBM, CPE adjustable from -30dBm to +20dBmVendor Y: BS adjustable from +22dBm to +35dBM, CPE adjustable from -27dBm to +24dBm
I just wanted to add to my previous message that apart from output power adjustmentthe dynamic range of ATPC is around 40dB to 45dB depending on vendors specification.
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T T G , R T G
In the standard 802.16 -2004 I found that TTG must be > to 200µs and RTG
> 5µs.
Must in reality, how long, in average, are RTG and TTG?
Transition Gap
Transmit/receive transition gap (TTG)
- A gap between the downlink burst and the subsequent
uplink burst in a TDD transceiver
- During TTG, BS switches from transmit to receive mode
and SSs switch from receive to transmit mode ( TDD switching timing:
( 13µs <> with SOFDMA modulation
Receive/Transmit transition gap (RTG)
- A gap between the uplink burst and the subsequent
downlink burst in a TDD transceiver
- During RTG, BS switches from receive to transmit mode
and SSs switch from transmit to receive mode ( TDD switching
timing 13µs <> with SOFDMA modulation
- The gap is an integer number of PS durations and
starts on a PS boundary
The IEEE specifications define TTG and RTG in terms of Physical
Slots. A Physical Slot (PS) is a duration calculated as:
PS = 4 / Fs
Where Fs is the sampling frequency, which can roughly be
calculated as Fs = n x BW. Where n is the sampling factor and BW is
the channel bandwidth. The values of n are available in the IEEE
specifications as well.
The WiMAX profiles released by the WiMAX Forum have a list of TTG
and RTG values (in terms of PS) for different channel bandwidths.
See
http://www.wimaxforum.org/technology/documents/WiMAX_Forum_
Mobile_S...
According to the profiles,
TTG = 296 PS for 10 MHz, 218 PS for 8.75 MHz, 376 PS for 7 MHz,
148 PS for 5 MHz and 188 PS for 3.5 MHz
RTG = 168 PS for 10 MHz, 186 PS for 8.75 MHz, 120 PS for 7 MHz, 84
PS for 5 MHz and 60 PS for 3.5 MHz
And, both should be at least 5 micro sec.
These values, of course, depend on the Frame Duration as well,
which is set to 5 ms by the Profiles.
The effect of TTG and RTG durations on coverage, or rather cell
coverage limit, comes from the fact that in TDD systems, if the
propagation time delay between the base station and the receiver is
higher than the lowest of the two values, i.e., Lowest(TTG, RTG), the
downlink and uplink subframes from different base stations will
overlap creating uncorrectable UL-DL interference. And, the receiver
will no longer be able to differentiate between the useful data it's
getting in DL from its base station, and the interference it is
receiving on the UL from nearby mobiles. Plus, the base station will
not be able to get the UL transmission from this mobile in time, i.e.,
it will receive the UL transmission from the mobile during the DL
subframe.
The coverage limit of cells with respect to the TTG and RTG
durations can be calculated as:
Maximum Coverage Range (m) = Lowest(TTG, RTG) x 300000 / 2
Where TTG and RTG are in ms, 300000 m / ms is the speed of
electromagnetic waves (speed of light, you can also use 299458.792
if you want ;-), and the division by 2 takes into account the round-
trip time.
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A S N P R O F I L E S
Attachments
16ng-4.pdf, 211 KB
technical_overview_and_performance_of_hspa_and_mobile_wimax_reva.pdf, 667 KB
Attachments
CarlbergDammander.pdf, 947 KB
Attachments
WiMAX_Network_Architecture.pdf, 3.1 MB
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C A L C U L A T I O N
Fade Margin Calculator is used for estimating the link energy parameters and
for upstream/downstream speed prognosis.
http://www.infinetwireless.com/Support/antenna_calc
http://www.calculatoredge.com/
http://www.rfglobalnet.com/content/misc/showdoc.asp?docid=
%7BFC228779-26E6-4B47-8C9C-73428BFBA44F
%7D&enableLeads=0&VNETCOOKIE=NO
http://www.lx.it.pt/cost231/final_report.htm
http://www.pizon.org/radio-mobile-tutorial/index.html
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C A P A C I T Y P L A N N I N G D I S C U S S I O N
Noise is a factor in the frequency domain (C/I) and the time domain (Eb/No-
minimized by multipath)
Signal to Noise Ratio can be improved by using multiple antennas (simple
diversity), maximum ratio combining, guard band between bits (to negate
the destructive effect of ISI), space time coding, Spacial multiplexing and
beam forming.
Since Wimax uses all of these techniques it is very difficult to determine
what state any particular carrier is in at any particular time. Adaptive
Modulation and Coding along with Adaptive Mode MIMO (switches between
matrix A-Space Time Block Coding and Matrix B-Spacial Multiplexing) provide
a system in a constant state of change.
The amount of multipath at each CPE cannot be predicted.
AAS shows the best ability (theoretically) of improving C/I but negates the
Inter Symbol Interference gains (ISI) of MIMO and guard bands (time).
Capacity considerations are: (using John Little's Law of Queueing)
Time in System = Waiting Time + Service Time
Number in System = Number Waiting + Number Being Served
Arrival Rate = Number Waiting / Waiting Time
Number being Served = Arrival Rate x Service Time
Number Waiting = Arrival rate x Time Waiting
Delay Probability = Link Utilization
etc, etc, etc..... It's a lot more difficult that using an Erlang B chart for voice.
I highly recommend attending the Wimax RF Designer Certification course
offered by the Wimax University if you are going to design and operate a
Wimax network.
A really good Wimax RF planning tool will be able to calculate capacity,
queueing, and take into account the effects of Adaptive Modulation and
Coding (BAND AMC), Adaptive MIMO (switches from Matrix A to Matrix B) and
closed loop MIMO (Beam Forming).
I look forward to your comments......
Coming from the TDM voice world to flat IP networks, it was unusual to
transition to a paradigm of soft-capacity (CDMA has soft capacity, but blocks
calls per Erlang B). The more load you put on an IP network, simply the
longer the packet delay. There's no blocking, the load is just absorbed
(unless you run out of buffer, which is a huge problem because it doesn't get
rid of the excess load, TCP just resends it on top of the other data already
trying to be sent, exacerbating the problem). This why call blocking (and
QOS) implemented on a VoIP network is so important (via SIP or proprietary
means), because if the load is too big, latency and jitter become intolerable,
and ALL calls get screwed.
Radio Resource Management systems are expected to be the most difficult
for vendors to develop (and biggest area of vendor differentiation). The
capacity of the system will be heavily dependent on these algorithms. It has
to marry pure capacity schemes (preference to high SNR) with fairness (low
SNR equally needing BW); throw in inter-cellular subcarrier sharing
(fractional reuse), 5ms traffic decisions ,and QOS, and it becomes a monster
traffic engineering problem. I've read of weighting algorithms whereby the
probability of getting resources is dependent on SNR and how long you've
been stuck in the Queue. What they try to do is wait and see if you get a
better SNR later on, so high SNRs get privileged in the short term (unfair, but
higher capacity vis-à-vis modulation/FEC state), but equal fairness in the
long-term. Fun, fun….
Some capacity-related docs attached...
Attachments
ChannelCapacity.pdf, 253 KB
CDC04.pdf, 119 KB
InOWo2004.pdf, 107 KB
There are many variations of throughput. Remember that the best modulation scheme is 64 QAM offering 6 bits / hz and the best coding scheme is 5/6. Give this perferc scenario the available throughput would be 25 Mb/s per sector. Of course not all users will be 64 QAM and 5/6, and not all of the sub-channels are used for data, so the actual throughput will be less. Adding MIMO will help to acheive the highest rate possible.
Here is a chart to help visualize the possibilities.
Attachments
OFDMA rates.jpg
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L I N K B U D G E T A N D P E N E T R A T I O N
The link budget is used to determine the maximum allowable path loss for a
BALANCED LINK. The purpose is to ensure that the CPE can talk back to the
base station.
The higher the frequency the faster the rate of attenuation, the less distance
covered. Remember
Path Loss = 32.45 + 20*log D(km) + 20*log F(Mhz)
WiMAX is not like CDMA with RW and no of RWs available to use. There is no
concept of RW per radio in WiMAX. In WiMAX, it is all about Service Flows
that can be supported in each radio. The larger the number of SF created in
a radio channel, the smaller each SF bandwidth will become. To counter this,
WiMAX support packet priority and CIR /MIR to allocate this valueable
resource accordingly (bandwidth) per SF.
64QAM means higher throughput but needs good SNR to achieve. BPSK is
less demanding on SNR and give you lowest throughput. This is the
modulation usually used for acquisition of the radio link to ensure the best
chance of getting a 2way comms with the BS. For BPSK operation at non LOS
condition (one brick wall blockage), the range could be 3-4km. General rule
of thumb is, a single brick wall gives around 10dB attenuation, metalise
window could give as much as 20dB attenuation. So if you can get 64QAM
operating at -70dBm, shuting a metalise window could drop you down to
BPSK operation.
1) Yes, you do have a link budget for each modulation scheme, more
specifically you would create a link budget for the Pilot/Preamble, UL/DL MAP
channels and then the UL/DL traffic channels with the most robust
modulation scheme. Choose the weakest link, and the MAPL from that will
define you cell range.
I recall a WiMAX Forum document with example link budget in this regard (I
beleive the title of the document contains "Part 1: Technical description").
2) I'm guessing you mean 3.5 and5.5 Ghz compared to the GSM
850/900/1800/1900 MHz bands. No doubt will you have much lower in-
building coverage/penetration with the higher WiMAX bands compared to the
GSM bands ...
At this stage you will seldom see any real link longer than, say, 5km, and in
this range a link budget is nicely established by power control. Everything
more than that is usually some experimental thing, and there is really no
point of rubbing in the 75Mbps at 30km any more - it washes off.
For any successful wireless business you simply MUST have most of your
users at QUAM 64 3/4 (or better :). To squeeze the most of it, you must have
some surplus juice (for power control), lowest possible installation (for better
reuse – steeper signal decay), cheap installations, and no antenna tilting.
Then it is perfect.
To do that, your footprint gets small, and in case of indoor it gets soooo
small that WiFi becomes equally viable solution.
Link budget 2.doc
mobile_wimax_deployment_alternatives.pdf
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R E C I E V E N O I S E F L O O R Q U E S T I O N
The RSSI for FIXED wimax says that measurable rx powers should be in the
range of -40 to -123 dBm.
My question is can we acheive a sensitivity of -123 dBm for any combination
of bandwidth and modulation scheme in wimax. BPSK 1/2 scheme requires a
SNR of 3dB. Hence the noise floor of the receiver should be around -126dBm,
if at all -123 dbM sensitivity can be obtained by BPSK using
subchannelization.
The noise floor values using the standard -174+10log(BW)+NF is higher than
-126 dBm for 1.25 MHz bandwidth.
Can someone please explain which modulation gives a -123 dBm sensitivity.
And also how the noise floor should be better, ie < -123 dBm.
-----
Related Answers:
Actually, it is possible to go deeper in case your receiver can sub-divide a
channel into smaller chunks, and thus reduce the BW component. However,
you can't go infinitely with this concept, and you are limited with
subchannelization to one single but whole subchannel, and this concept
might make sense only in case you have multiple receivers (for pilots, etc.)
-123 dBm (with 3 dB SNR) stands for 63kHz bandwidth, and it is reduced
somewhat in case of a realistic receiver NoiseFigure of ~4dB - down to
25kHz. It is just about enough to encompass a whole subchannel in a 3.5Mhz
OFDM channel.
These multiple receivers are realised via serious DSP computing, and it is
somewhat different than the original FFT concept of OFDM. What goes
around - comes around.
WiMAX don't have BPSK scheme, I think QPSK 1/2 repetition 6 would be most
robust MCS in WiMAX.
I don't know the meaning of "measurable". Does this mean "decoderble"?
And, I can't believe the sensitivity of any MS in WiMAX can meet -123dBm.
It's really perfect one.
I think -123dBm only consider AWGN noise and very very good SNR.
Normal situation in field does not show the 10dB SNR(example of good
signal) and -123dBm RSSI.
-123 dBm means the edge of cell and SNR would be going to 0dB or negative
SNR.
And, required SNR of data burst and preamble or control signals are different
also.
Anyway most robust one is QPSK 1/2 repetition 6.
There are some things one must separate mentally when considering any
technology, otherwise it all falls into apples-pears kind of confusion.
Remember the 20 miles and 70Mbps tantrum? If all calculations are done
correctly you'll always get the same result, regardless of the approach. The
only necessary thing is to keep your apples together from beginning to the
end, OR pick pears and stick with them to the end.
How it works? All communication can be expressed as energy per bit. Energy
for all bits over full bandwidth running at some bitrate is total power of a
system (apples). It can be seen as power density divided into sub-bands, and
you get portions of power over smaller bandwidths with single subchannel as
a unit (pears). Whatever approach you pick - end result is the same.
Point with OFDMA is that using small total power divided into small number
of carriers you can reach further. To facilitate calculation it is customary to
observe a single subchannel's behaviour (pears). Nothing else.
You should find exact meaning of -40~-123 dBm
I think -123 dBm is come from "dBm per minimum data burst unit(It's termed
tone in WiMAX)
I don't know exactly what FFT size is used in 1.25MHz BW.
If 128 FFT is used in your system, -134 dBm is calculated from your formula.
And -40 dBm may be come from full BW usage.
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M O D E L T U N I N G P R O C E D U R E
1. Set your planning tools correctly, i.e. Equipment, Antennae masks, output
powers, etc...
2. Focus on one region, which contains the major clutter types: dense urba,
suburban, rural...etc...
3. Examine your map data and preferably you should get map data with high
resolution. Set the inital clutter attenuations as they are very important.
4. Run a simulation and produce a coverage plot.
5. Go on drive tests in this area.
6. Visualize the drive tests and run a report to see the delta between the
planned and measured data. Chech the error report as well, (RMS...)
7. Edit some of the parameters in the propagation model and some of the
clutter attenuations.
8. Run a coverage plot again.
9. Go on drive tests, visualize and prdouce comparison report.
10. if you fit in less then 5dB error from the simulation, you have done well. If
not...continue working.
Model tuning is very very demanding in terms of knowledge and experience,
but you must strive to do it. This is the way. Also I am again asking to refer
to the other topics on this. There are very good detailed explanations.
1. ALL models work as more or less linear functions against the log distance.
When tuning a model, you need at least a whole decade of distance included
in your drive test (e.g. 100m to 1km, or 300m to 3km), and your drive test
points density must be spread linearly against the log distance. This requires
as many points you can gather near to the base station, and only a selected
few on different clutters at far side.
2. Always perform Lee transform (decimation) prior to model tuning to
exclude Rayleigh from equation.
3. Validity of a model is checked by filtering out a group of points that have
some distinct feature, e.g. LOS, and see if your average difference
(measured against model) remains zero. If not - try harder.
4. RMS errors smaller than 7 dB are fine.
5. Do it by hand, and tune a single parameter at one time, observe RMS error
average difference, and if possible observe a difference distribution plot - if
you observe two or more distinctive "hills" there - your cartography may be
wrong or your clutters are not selected appropriately.
6. Take time.
A final report of COST-231 can be downloaded at:
http://www.lx.it.pt/cost231/final_report.htm
Mr. Coreia usually makes a book out of a final report, and sells it while it is
hot. This one is not that hot any more, and it is a perfect starting point for
serious researcher. Unfortunately OFDM is not included.
About the Lee criterion and how to collect and decimate drive test data see
this: http://whitepapers.zdnet.co.uk/0,1000000651,260090593p,00.htm and
it requires a free registration
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W I M A X S P E C T R U M E F F I C I E N C Y
The capacity of each sub carrier depends on the modulation order, which can
be BPSK (1 bit per sub carrier), QPSK (2 bits per sub carrier), 16QAM (4 bits
per sub carrier), or 64QAM (6 bits per sub carrier) in the case of the OFDM
PHY. In general more power is required for using higher order modulation in
order to achieve the same range performance.
In the OFDM PHY there are 256 sub carriers spanning the sampling spectrum
which is defined as:
Eq. 1) Fs = FLOOR(n · BW / 8000) · 8000 ,
Where n is the sampling factor, a constant dependent on the channel size,
and BW is the channel size in units of Hz. The number of sub carriers
corresponds to the size of the FFT/IFFT used to receive and transmit the
OFDM symbols. To reduce the complexity of the digital processing algorithms
it is desirable to use FFT sizes that are powers of 2.
For channels in the 3.5 GHz band the licensed channels are multiples of 1.75
MHz and n = 8/7. For a channel width of 3.5 MHz the sampling spectrum is
4.0 MHz. The 256 sub carriers are equally distributed across the sampling
spectrum implying a spacing of:
Eq. 2) Δf = Fs/256 .
For example Δf = Fs/256 = 15,625 Hz for a 3.5 MHz channel.
Notice that changing the channel width changes both the sub carrier spacing
and the symbol time. This implies a range of practical channel sizes for fixed
applications but quickly becomes unworkable for mobile applications where
the design approach of scaling the FFT size to the channel width is used with
the OFDMA PHY.
In order to provide increased inter-channel interference margin and ease the
radio filtering constraints, not all of the 256 sub carriers are energized.
There are 28 lower and 27 upper “guard” sub carriers plus the DC sub carrier
that are never energized. Of the 256 total sub carriers therefore, only 200
are used which leaves a total occupied spectrum of Δf · 200 = 3.125 MHz for
a 3.5 MHz channel.
This example implies a raw, occupied bandwidth efficiency of 89% (3.125/3.5
= 89%), but the number varies for other channel bandwidths and sampling
factors. This is the first example we have encountered of what can be
considered to be channel overhead that decreases the channel capacity, in
this case it is required by design to improve the channel quality when
adjacent spectrum is occupied.
Not all of the 200 occupied sub carriers are used to carry data traffic. There
are eight pilot sub carriers that are dedicated for channel estimation
purposes, leaving 192 data sub carriers for user and management traffic. In
order to calculate the raw channel capacity it is useful to understand how
many bits each data sub carrier can carry.
The raw sub carrier capacity, before taking out the overhead added by
redundant error correction bits, is given by the modulation order: 6 bits/sub
carrier for 64QAM, 4 bits/sub carrier for 16 QAM, and so on. For example, a
channel able to support 64QAM modulation could send six bits for each data
carrier per symbol. But how long is a symbol?
The orthogonality of the sub carriers is achieved by maintaining an inverse
relationship between the sub carrier spacing and the symbol time. So the
useful symbol time is just the inverse of the sub carrier spacing:
Eq. 3) Tb = 1/Δf.
For example, a 3.5 MHz channel has a useful symbol time of 1/15625 = 64
us. However for multi-path channels, we must make allowances for variable
delay spread and time synchronization errors. In OFDM, this is accomplished
by repeating a fraction of the last portion of the useful symbol time and
appending it to the beginning of the symbol for a resulting symbol time of:
Eq. 4) Ts = Tb + G · Tb,
Where G is a fraction:
Eq. 5) G = 1/2m, m = {2,3,4,5}.
The repeated symbol fraction is called the “cyclic prefix”. Larger cyclic prefix
implies increased overhead (decreased capacity since the cyclic prefix
carries no new information) but larger immunity to ISI from multi-path and
synchronization errors.
For a 3.5 MHz channel the useful symbol time is 64 us and the minimum total
symbol time is Ts = 64 us + 64/32 us = 66us. The raw channel capacity per
symbol is:
Eq. 6) Craw = 192 · k / Ts,
Where k is the bits per symbol for the modulation being used.
Assuming 64QAM modulation (6 bits per symbol):
192 data sub carriers x 6 bits/sub carrier / 66 us = 17.45 Mbps.
Notice that the modulation rates are designed so that an FEC coded block
just fits in one symbol time when all 192 sub carriers are used.
For instance for 64QAM, 144 Bytes = 1152 bits / 6 bits/symbol = 192 sub
carriers.
The useful channel capacity per symbol is:
Eq. 7) C = Craw x OCR,
Where OCR is the overall coding rate given in the table. For example, for a
3.5 MHz channel the useful channel capacity per symbol assuming the
highest rate modulation and coding is:
C = 17.45 Mbps x 3/4 = 13.1 Mbps.2
It is useful to summarize the discussion of the channel capacity is terms of
the spectral efficiency. Spectral efficiency is expressed in units of bits per
second per Hz and is obtained by dividing the channel capacity by the
channel width:
Eq. 8) E = C / BW.
We can see that our 3.5 MHz channel has a spectral efficiency (so far) up to
13.1 Mbps / 3.5 MHz = 3.74 b/s/Hz. The spectral efficiency is a useful figure
of merit to keep in mind because it lets you quickly calculate the capacity for
other channel sizes that WiMAX supports.
2 By now at least some readers must be wondering what happened to the
often-hyped 75 Mbps channel capacity for WiMAX? Taking the very largest
channel size, 20 MHz, highest coding rate, and minimum cyclic prefix, the
raw channel size using equation 6 is: Craw = 192 x 6 b/sub carrier / 11.3 us
= 102.0 Mbps.
The useful channel size from equation 7 is: C = Craw x ¾ = 76.5 Mbps. Of
course we have said nothing about the (short) range of such a hypothetical
channel, and we should be aware that this is before taking out other PHY and
MAC layer overhead that, as we will see, is significant. To be blunt, talking
about 75 Mbps WiMAX channels for MAN applications is about as meaningful
as quoting the top end speed marked on the speedometer of a family
minivan.
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U L T R A C O M P A C T 2 G / 3 G D U A L - M O D E R F T R A N S C E I V E R
US : Renesas Technology America, Inc. today
announced the R2A60281LG, an ultra-
compact 2G/3G dual-mode radio frequency
(RF) transceiver that supports both the 2G
and 3G modes used in cellular
communications. The device integrates in a
single chip most of the high-frequency signal
processing functions required by mobile
phone handsets, including the down
conversion of high-frequency wireless signals
to a lower frequency to be used by the
baseband processor.
The R2A60281LG is only 7×7×0.6 mm
(about 20% smaller than previous solutions). It combines multiple functions
and eliminates the need for an analog baseband processor. Therefore, it will
facilitate the development of smaller and thinner handsets for GSM and W-
CDMA/HSUPA/HSDPA networks used as the global mobile telephony
standards. The transceiver also can be applied in 3G communication cards
for PCs.
Multiple industry trends are driving the need for the new transceiver. Many
mobile phone users are expected to replace older phones with global 3G
models that also support the GSM (2G) standard. At the same time, there is a
growing demand for handsets that support more than one frequency band.
Feature-rich handsets offering an array of multimedia functions, such as
terrestrial TV broadcast reception, are becoming more popular, making it
necessary to mount more electronic devices on handset circuit boards, even
as the handsets themselves become thinner. The new transceiver builds on
previous Renesas RF transceiver technology and addresses these trends by
supporting multiple frequency bands and both the 2G and 3G modes, while
also offering faster operation and a smaller, thinner package.
Specifically, the R2A60281LG integrates 2G (GPRS/EDGE) quad-band
(850MHz/ 900MHz/ 1.8GHz/ 1.9GHz) and 3G (W-CDMA) quad-band (800MHz/
1.5 GHz/ 1.7 GHz/ 2 GHz) functionality into a single chip. It also supports
High-Speed Downlink Packet Access*1 (HSDPA) categories 7 and 8 for fast
data downloads at speeds up to max. 7.2 Mbps as well as High Speed Uplink
Packet Access (HPUPA). The chip is built in 0.18 micrometer Bi-CMOS
technology.
The transceiver includes the low-noise amplifiers (LNAs), a loop filter*2
circuit, HPA controls and more. A filter supporting CDMA2000 attenuates
wavelengths outside the desired frequency band, reducing susceptibility to
radio frequency interference (RFI). Also, a 312Mbps (max.) digital interface
function supports 3G DIGRF operation, offering the A/D and D/A conversion
functions formerly handled by an analog baseband processor. This interface
enables high-speed exchanges of In-Phase/Quadrature-Phase (I/Q) and
control data with a digital baseband processor, for quick transfers of large
data volumes.
The R2A60281LG 2G/3G dual-mode RF transceiver looks to the future, as
well, by also supporting the 1.5GHz band under the specifications newly
standardized by the Third Generation Partnership Project (3GPP), an
international body for establishing 3G mobile phone standards. Renesas’
development plans for RF transceiver products include new chips offering
support for the 3G-LTE*3 and 4G modes that will enable even faster
communication speeds.
Prices and Availability
Product
Name Package
Sample Price/
Availability
R2A60281LG 120-pin
LGA $9/ March 2008
Note 1 HSDPA: High-Speed Downlink Packet Access. This high-speed
s: .
packet communication standard is an extension of W-CDMA. It can
be thought of as 3.5G relative to 3G. HSDPA supports downlink
packet communication at speeds up to 14.4Mbps. Category 8
supports a maximum data transfer rate of 7.2Mbps.
2.
Loop filter circuit: The circuit that determines the frequency
characteristics of the phase locked loop (PLL) circuit, which controls
the oscillator. The input signal is compared to a signal generated
internally by the circuit in order to detect shifts in frequency or
phase. The detected error is fed back to the oscillator, and the
output signal is generated. A loop filter circuit requires a high level
of calibration accuracy.
3.
3G-LTE (Long-Term Evolution): The terms "3G Long-Term Evolution"
and "Super 3G" are both used. The system supports maximum
communication speeds of 100Mbps for downloads and 50Mbps for
uploads.
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M O B I L E W O R L D C O N F E R E N C E A N N O U N C E M E N T S
The Mobile World Congress 2008 moves into high gear today, bringing
together some 13,000 companies and 100,000 visitors in Barcelona. The
GSM Association, which sponsores the show, is the global trade association
representing more than 690 GSM mobile phone operators across 214
territories and countries of the world.
Google’s Android mobile platform will be demonstrated (video) on a Texas
Instruments-powered handset while new handsets are being rolled out by
Sony Ericsson, with 10 new phones, Samsung with eight new products, and -
megapixel camera uploads directly to Flickr with geotagging.
Nokia four new mobile phones. The Sony Ericsson C702 Cyber-shot uses
built-in aGPS to stamp location data onto every photo you take with its 3.2
MP camera and the Nokia 6220 5-megapixel camera uploads directly to Flickr
with geotagging. LG Electronics and LG-Nortel are demonstrating how LTE
can deliver high-speed wireless Internet.
Some of the announcements today include:
Kineto Wireless is creating a UMA-enabled 3G solution based on NXP’s Nexperia UMTS chips. Unlicensed Mobile Access dual-mode handset services are now focused on delivering UMA phones with 3G capability,” said Ton Van Kampen, vice president of business development for NXP. Kineto’s UMA client software allows customers to seamlessly roam and handover between the cellular 3G UMTS network, the 2.5G GSM/EDGE network, and home or enterprise Wi-Fi access networks.
Broadcom announced a chip offering support for the three most popular open operating systems for smartphones - Symbian, Windows Mobile and Linux. Broadcom also announced a reference design that brings advanced handset features to mass market including a 3.2 megapixel camera with GPS, Wi-Fi, Bluetooth and FM.
Motorola will showcase their ROKR E8 and MOTO Z10 and license its mobile WiMAX chipset reference design, the Motorola WTM1000, and essential IP licenses for the company’s portfolio of patents to third parties in a move designed to encourage the innovation and proliferation of new WiMAX-enabled devices. Motorola also unveiling its first WiMAX chipset reference design licensee. Enfora, a leader in wireless monitoring and asset management applications, plans to integrate the Motorola WTM1000 solution into its suite of eWiDE wireless networking solutions. The WTM1000 chipset-based radio is scheduled to debut in Motorola’s line-up of WiMAX mobile devices for various carriers around the world, including Sprint Xohm.
Sierra Wireless added two new products to its lineup of HSPA mobile broadband modems, the AirCard 885E ExpressCard and the Compass 885 USB modem for use worldwide.
NEC is connecting real world phones to the “Second Life” with their IP Voice and Media Solution. Visitors can enter Second Life and control an
avatar to make calls to another person in the real world by using the NEC communicator.
The WiMAX Forum will hold a media luncheon and news event on the “State of the WiMAX Industry” in Barcelona. This event plans to address expected WiMAX device availability, global network deployments, and updates on mobile certification.
Alvarion announced they will be the first WiMAX vendor to join the HP Developer and Solution Partner Program. Alvarion will demonstrate its end-to-end 4Motion Mobile WiMAX solution based on HP software at Mobile World Congress in Barcelona.
Nokia’s new dual-band HSDPA N96 doubles internal memory to 16GB from the N95, while adding LED lights to the 5 megapixel digital camera for flash and video lighting.
Samsung’s Ultra III U900 “Soul” is a metal-encased slider, only 12.9 millimeters thick, with a 5 megapixel digital camera and face detection along with Bang & Olufsen sound.
Nortel Networks and Motorola both had live LTE radio networks running at the conference, while Qualcomm announced it would begin shipping multimode LTE-CDMA and LTE-UMTS chipsets in 2009.
Cisco will showcase mobility applications to change the way people connect, collaborate and access entertainment on the move including DVB-H, Three-Screen Video and VoIP for Mobile Operators. The Cisco WiMAX Radio demonstration included the Cisco BTX-MX8 WiMAX Basestation, the RFS8 Antenna System, and a selection of Cisco and third-party subscriber stations (customer premises equipment [CPE])
The GSM Association announced that it is partnering with Mofilm to present a short film showcase for mobile phones. The partnership follows the success of last year’s experimental Sundance Film Festival: Global Short Film Project, a collaborative pilot between Sundance Institute and the GSMA.
Mobile Television announcements included an announcement by Carriers Orange and T-Mobile to rollout of a broadcast mobile TV service in the UK this year using existing cellular spectrum and the TDtv technology developed by embedded-software-systems provider NextWave Wireless. Meanwhile, Nokia’s new N-96 featured a built-in DVB-H receiver for digital TV signals in Europe and Asia.
Texas Instruments said it had developed a chip to support cell phones with mini projectors and another chip that would let users record high-
definition video on their phones. TI claims it’s pico projector chips are ready for production.
Qualcomm introduced a slew of new chips including an integrated ARM11 applications processor running at 528 MHz, a multimedia chipset, a seventh-generation gpsOne engine with support for Standalone-GPS and Assisted-GPS modes, and support for Bluetooth, Wi-Fi and FM radios.
Wi-Fi hotspot aggregator Boingo announced an unlimited-use, $7.95-per-month plan for its entire global network of 60,000 hotspots at the 3GSM cell phone trade show today. The inexpensive plan will work on cell phones, PDAs, and a Belkin Wi-Fi phone—just not on laptops. It’s truly $7.95 for unlimited use, according to Boingo’s Jonathan Mendelson.
Spotigo’s Wifi-based Positioning Solution can now be downloaded free from their website. Any WiFi device can be located just by the received WiFi signal patterns.
Nokia made a big splash with its Media Network, an alliance of more than 70 publishers and operators including Sprint, Discovery, Hearst and Reuters. The company claims ads are already yielding average click-through rates of 10% with a potential reach of 100 million mobile consumers. It leverages analytics technology from Enpocket, which Nokia acquired last year. Comverse launched a mobile advertising solution to deliver ads through text, multimedia messaging, visual voicemail, ringback tones and on the wireless Internet while Ad-funded mobile game publisher Greystripe reported a click-through rate of more than 4% during a two-month campaign for Yahoo Inc.’s oneSearch mobile Web portal.
Worldmax, a new broadband wireless access provider in The Netherlands, has selected communications solutions provider Alcatel-Lucent to deploy one of the first commercial WiMAX 802.16e-2005 networks in Western Europe, in Worldmax’s 3.5GHz spectrum.
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A W S L I G H T S U P T E X A S
Stelera Wireless, an Oklahoma City-based rural broadband service provider
has launched Advanced Wireless Services (AWS) in Floresville and Poth,
Texas, notes Om Malik.
Stelera is a wireless startup that is focused on
delivering broadband services in rural
communities. It owns 42 AWS licenses across the
United States covering almost 6 million people. It
is the first mobile operator to utilize the AWS
band (2.1 GHz and 1.7 GHz) in the United States.
The company will offer residential and business packages that cost anywhere
from $60 to $100 a month. The speeds on an HSPA network are up to 7.2
Mbps downlink and 2 Mbps uplink. The I-HSPA technology from Nokia
Siemens Networks can offer download speeds of up to 42 megabits per
second. Stelera owns 42 AWS licenses across the U.S., mostly in rural
communities.
Leap Wireless is another AWS operator poised to
make a large push into East Coast and Gulf Coast
markets using its AWS spectrum notes RCR News. Leap owns AWS spectrum
along the Gulf Coast, from Corpus Christi, Texas, to Baton Rouge and New
Orleans, La. The East Coast cities where Leap expects to build new markets
include Wilmington, Del.; Philadelphia, Pa.; Washington, D.C.; Baltimore, Md.;
and Richmond and Norfolk, Va.
More recently, Leap and MetroPCS announced a merger, that brought two
large AWS spectrum owners into more direct competition with the largest
AWS spectrum owner in the United States — T-Mobile.
Headquartered in San Diego, Leap Wireless began as a spin-off of
QUALCOMM and now owns licenses for 35 of the top 50 markets, including
Chicago, Milwaukee, Minneapolis, Philadelphia, Washington D.C, and Seattle.
Leap ended 2007 with approximately 2.86 million customers.
MetroPCS, headquartered in Dallas, has more than 3 million subscribers and
holds 23 licenses through its subsidiaries in the South and Central Florida,
Atlanta, San Francisco, Dallas, Detroit and Sacramento metropolitan areas.
Both MetroPCS and LeapWireless (under the Cricket name) acquired
nationwide spectrum in the AWS auction last year.
Top 10 Highest AWS Bidders
BiddersNet total of high
bids1. T-Mobile $4.2 billion
2. Verizon Wireless $2.8 billion3. SpectrumCo $2.4 billion
4. MetroPCS $1.4 billion5. Cingular $1.3 billion6. Cricket $710 million7. Denali Spectrum
$365 million
8. Barat Wireless $127 million9. AWS Wireless $116 million
10. Atlantic Wireless
$81 million
Click here to find out who is backing these bidders.
The FCC’s Advanced Wireless Services auction concluded in September 2006
and grossed $13.9 billion for the U.S. Treasury.
The big winner of AWS spectrum was T-Mobile, which spent some $4 billion
covering virtually the entire country.
As an aside, some observers believe going beyond the $4.7 reserve price for
nationwide 700MHz coverage would be imprudent. But considering you only
need one third the towers at 700MHz for similar coverage, it could be a
comparative bargain. Because 700 MHz is “open”, unlike the AWS band, it
might be tougher for an operator like Verizon or AT&T to rationalize.
But without a legacy cellular network to protect — and a mobile advertising
platform to generate revenue — 700 MHz could be a license to print money
for someone like Google. Research firm Gartner predicts worldwide mobile
advertising revenue will grow from less than $1 billion last year to $11 billion
in 2011.
In related news, Nokia Siemens Networks was also selected by satellite
phone company TerreStar Networks, to deploy Internet-HSPA solution for the
TerreStar all-IP integrated satellite and terrestrial wireless communications
system.
“We don’t have to deal with all of the highways and byways that cellular
carriers have,” said Dennis Matheson, chief technology officer for TerreStar.
“But satellites can’t get to the mass consumer because they disappear into
urban canyons. So we need the HSPA network to fill in the gaps.”
Nokia Siemens says it will be the first commercial I-HSPA network
deployment, a technology that Nokia Siemens helped pioneer.
Their Flexi WCDMA Base Station uses an Internet-High Speed Packet Access
(I-HSPA) architecture, which eliminates legacy circuit-switched technology.
Optimized for native IP applications, including voice and data, I-HSPA is the
only commercially available all-IP solution, and is optimum for edge
deployment within TerreStar’s MSS service, says the company.
“I-HSPA still isn’t a replacement for WiMAX, not providing the bit-per-hertz
efficiency of the OFDMA technology, but it’s not intended to be”, said Mark
Slater Nokia’s VP of sales, in Telephony Magazine. Nokia, in fact, is straddling
both sides of the fence, building a WiMAX portfolio in parallel with its UMTS
(3G) cellular portfolio.
Devices normally connect through a base station and then are routed
through specialized cellular gear before finally hitting the Internet. I-HSPA
eliminates much of that cellular gear, allowing the device to connect directly
to the Internet through a base station. Smooth handoffs between ajoining
cell sites is said to be the downside.
TerreStar Networks, a satellite phone company, will leverage Nokia Siemens
Networks’ I-HSPA technology as the foundation for development of their LTE
(Long Term Evolution) services.
When TerreStar’s network is deployed, perhaps later this year, the company
will provide universal access and tailored applications to millions of users
throughout North America via mass market commercial wireless devices and
spot beams.
TerreStar, which just announced $300 million in investor commitments
through the launch of its hybrid mobile satellite, said Arianespace, the launch
provider for TerreStar-1, has confirmed it can launch the satellite during the
December 2008 through February 2009 launch window.
Competitor ICO also shares those
MSS frequencies and
boardchairman Craig McCaw would
like to use ICO’s frequencies to
carry mobile television as an
adjunct to Clearwire’s Mobile
WiMAX.
ICO plans to integrate its Mobile
Interactive Media (MIM) suite of
services with Clearwire’s
broadband network. “Our next generation wireless personal broadband
networks are built to deliver data, voice and video over a single network,”
said Scott Richardson, chief strategy officer for Clearwire.
If Craig McCaw’s ICO can deliver live television to mobile DVB-SH receivers,
who needs MediaFLO? Probably not Clearwire — or possibly Sprint’s Xohm.
ICO’s first GEO satellite is scheduled to be launched in early 2008 with MSV’s
hybrid service starting in 2009.
ICO’s G1 satellite is due to launch on an Atlas V launch next month by United
Launch Alliance. ULA, by the way, is the product of a merged Evolved
Expendable Launch Vehicle program (EELV) that stuck taxpayers with a
$14.4 Billion bill for cost overuns due to Lockheed and Boeing’s duplicative
rocket programs that ballooned from $17 billion to $32 billion in a few years.
Clearwire, a partner with Intel and Motorola, is committed to Mobile WiMAX,
but I-HSPA handsets could be one option for AWS spectrum holders T-Mobile,
Verizon and AT&T — featuring dual-mode AWS/satphone connections.
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M O B I L E W I M A X A T W O R L D C O N G R E S S
The WiMAX Forum today announced that 28 Mobile WiMAX products in the
2.3 GHz and 2.5 GHz frequency bands have been submitted for WiMAX
Forum certification since WiMAX Forum labs began accepting applications
from vendors in late 2007. The first Mobile WiMAX products are expected to
achieve the WiMAX Forum Certified seal of approval in Q2 2008 and to reach
the market later this year.
The organization also announced its official support for Mobile WiMAX
certification in the 700 MHz band. Work on the technical specifications for
700 MHz WiMAX Forum certification is already underway in the association’s
working groups. The published specifications will be unveiled as they are
completed and they will support both TDD and FDD certification profiles.
“With more than 260 commercial WiMAX deployments rolled-out on a global
basis, WiMAX technology is the only commercially available OFDMA-based
wireless technology,” said Ron Resnick, president of the WiMAX Forum.
The WiMAX Forum media luncheon featured testimonials from global service
providers, including Freedom4, Iberbanda, KDDI, Korea Telecom and
SprintNextel and who each indicated the readiness of WiMAX technology
with certified products and the optimization of WiMAX networks for
broadband data services as key motivators in selecting WiMAX technology
for their next generation services.
TelecomTV has video reports from Mobile World Congress 2008 (above).
Other WiMAX announcements at the big show in Barcelona:
Redline Communications introduced a full suite of RedMAX 4C Mobile WiMAX products including Mobile WiMAX base stations and subscriber devices for the 2.5 GHz and 3.5 GHz bands. The expanded RedMAX 4C familyx includes Redline’s 2 x 2 MIMO antenna technology which is said to deliver equal performance to competitive 4 x 2 systems, providing greater coverage and a lower absolute cost to operators.
Alcatel-Lucent announced Mobile WiMAX contracts with Worldmax in the Netherlands and Packet One in Malaysia as well as several additional operators yet to be publicly disclosed. Alcatel-Lucent’s commercial 16e deployments worldwide now total 22 - more than any other vendor claims the company.
Intel, through its VC funding arm, said it will make a “substantial” investment in Freedom4 (right), a London-based WiMAX service provider.
The U.S. Army is testing Mobile WiMAX. They took three Samsung base stations and mounted them into Humvees, connected to a satellite link as the backhaul. It is believed to be the first time a satellite link was used with WiMax. Military forces can set up a satellite dish and pop up a WiMax antenna next to it to form “a bubble of WiMax” around a particular area or a convoy, according to testers.
Mitsumi is using Sequans chips for Mobile WiMAX modules in an SD card. The SD card includes all Mobile WiMAX functionality in a small 20X20 mm package.
SEQUANS and Tecom LTD, a leading telecommunications equipment manufacturer of Taiwan, have introduced a comprehensive Tecom WiMAX product series including Mobile WiMAX Wave 2 base stations and subscriber stations using Sequans chip solutions as the main design platform.
Max Telecom today announced it has completed the first phase of its WiMAX rollout in Bulgaria, using the Cisco Mobile WiMAX technology paired with its access and aggregation solutions. Max Telecom plans to expand coverage to 90 percent of Bulgaria’s population by the end of 2009.
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B A R E N U C K L E S I N B A R C E L O N A : L T E V R S W I M A X
At the Mobile World Congress in Barcelona, the showdown pitting upstart
Mobile WiMAX against Long Term Evolution, backed by heavy weight telcos,
is going head-to-head. At stake is a huge global market for 4G telecom gear
and services that could dwarf today’s 3G.
China Mobile announced today that it will join Verizon Wireless and Vodafone
in a three-way operator trial of Long Term Evolution (LTE), the 4G mobile
broadband standard, says Light Reading. China Mobile is the world’s largest
mobile operator, with over 350 million customers, and may tip the 4G
standards scales in LTE’s favor.
Along with Verizon and Vodafone, the operator joins the ranks of NTT
DoCoMo, which has an aggressive LTE deployment plan and AT&T, which is
expected to make a committment to LTE but has not made it official (yet).
Alcatel-Lucent also announced it is teaming with Japan’s NEC in a joint LTE
venture. Alcatel-Lucent CEO Patricia Russo (left), said the move is an
offensive play, rather than a defensive one.
“It’s about scale, time to market, and pooling existing R&D,” she told
reporters during an afternoon press conference at the Mobile World Congress
in Barcelona, Spain. “This is not a way to reduce our investment.”
The China Mobile trials will
focus on both the frequency-
division duplex (FDD) and time-
division duplex (TDD) varieties
of the LTE standard. The TDD
version of LTE is China Mobile’s
technology choice because it is
an evolution of the Chinese
homegrown 3G standard, TD-
SCDMA.
LTE is a telecom-centric
project. It is not a standard yet,
but it is expected to mold the
new release 8 of the UMTS IP-based standard. LTE’s overriding characteristic
is many telco layers and proprietary protocols.
Most observers believe WiMAX has a 2-3 year lead over LTE.
That may have prompted GSM Association CEO Rob Conway to opine that
WiMAX should become a subset of LTE.
WiMax supporters say it should be the other way around.
“We went from having virtually no products here in Barcelona last year to
having over 40 companies with real products on their stands, so Wimax is
here and it’s real,” said Wimax Forum president Ron Resnick.
Resnick said 28 Wimax products in the 2.3 GHz and 2.5 GHz frequency bands
had been submitted for Wimax Forum certification since the forum’s labs
opened for business late last year (pdf). The forum is aiming to certify 100
products for interoperability by the end of this year, and 270 by 2010 – not
including CPE gear. The industry body, which lists almost 540 member
companies, promoted a walking booth tour of over 40 companies at the show
demonstrating Wimax equipment.
Cisco’s John Chambers predicted at the Mobile World Congress that by 2011,
WiMax will account for 10 to 15 percent of wireless traffic.
GSMA chairman Craig Ehrlich has been
openly critical of the Wimax business case,
describing it as too little, too late in the face
of escalating HSDPA rollouts and the coming
of LTE. Officials at China’s MII attacked
Wimax’s inclusion last October as an IMT-
2000 standard, seeing it as a rival to their homegrown TD-SCDMA
technology.
According to the GSM Association, about 80% of cellular users world-wide
use the GSM (Global System for Mobile communications) technology, or more
than 2.5 billion people. A total of 3.3 billion people — more than half the
world’s population — now use cell phones. Revenues, which totaled $125Bn
in 2007, are expected to reach $200Bn by 2011. Intel sees a $10 billion
mobile chip market by 2011.
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F O O T B A L L E R G E T S O W N 3 G M O B I L E T V C H A N N E L
Orange announced the launch of Frank TV, a mobile channel dedicated to
England and Chelsea star Frank Lampard. Frank TV will be available
exclusively to the 1.3 million Orange 3G customers on its mobile phone TV
service - Orange TV, and will be up alongside other Orange mobile TV
channels including BBC, Channel 4, Sky and FHM.
Frank TV features never-before-seen footage from Frank’s video diaries
which he filmed over the past two seasons, giving exclusive behind the
scenes access to Stamford Bridge, the Chelsea training ground, Frank’s
house, pets and much more. There are also special guest interviews with
Frank Lampard senior, Jamie Redknapp and Lawrence Dallaglio.
Jake Redford, Head of Mobile TV, Orange UK said: “We are delighted to
launch a dedicated channel to arguably one of the most committed and
professional midfielders in world football. Frank TV makes for great bite-size
viewing and provides our mobile TV viewers unique insight to the life behind
the footballer”.
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M A K I N G T H E C A S E F O R 3 G L T E - G L O B A L M O B I L E B R O A D B A N D
US : A new report published by the UMTS Forum predicts that LTE (Long
Term Evolution) - Global Mobile Broadband could generate total revenues of
€150 billion for operators by 2015.
The new report - titled Global Mobile Broadband: Market Potential for 3G LTE
- forecasts that smooth evolution from today’s investments in 3G UMTS
(WCDMA/HSPA) will kick-start a new wave of high-speed interactive services,
strengthening ARPU in many mobile markets.
Specifically, the report predicts that subscriptions to LTE - Global Mobile
Broadband networks will exceed 400 million by 2015, or double today's
number of WCDMA/HSPA customers. Furthermore, revenues from LTE -
Global Mobile Broadband will represent more than 15% of all mobile
revenues that are predicted to approach €1 trillion globally in 2015.
While it's expected that Western Europe and developed Asia will account for
the majority of LTE - Global Mobile Broadband customers, the report
forecasts strong uptake in developing markets by 2015.
While non-voice services currently represent just 10-15% of revenues in
developed markets, the study suggests that LTE - Global Mobile Broadband
will drive this proportion to 36% by 2015.
The report is based on original research conducted for the UMTS Forum by
Analysys Research (www.analysys.com), who modelled future demand for
global mobile broadband by extrapolating current market trends.
With technical specifications for LTE now stabilised within the Third
Generation Partnership Project (3GPP), it's an anticipated that the first LTE -
Global Mobile Broadband networks will be commercialised in 2010. Wide-
scale rollout is anticipated from 2011.
Building on current investments in the GSM/UMTS Evolution ‘family’ of 3GPP
systems, LTE - Global Mobile Broadband provides a smooth evolutionary path
to far higher data speeds and lower carriage costs with more efficient,
flexible use of operators' radio resources.
With more than 165 HSPA networks already commercialised or in
deployment, 3GPP’s significant global footprint will support a future mass
market for high-speed, high capacity services at significantly lower cost than
greenfield investment in other broadband wireless systems.
Enabled by SAE (Systems Architecture Evolution) that offers a 'flat' all-IP
architecture, LTE - Global Mobile Broadband also promises lower latency that
will support multiplayer gaming, social networking, high-quality
videoconferencing and a new generation of other real-time interactive
applications. The report also predicts that LTE - Global Mobile Broadband’s
low latency and reduced per-bit costs will drive the development of remote
monitoring and other machine-to-machine (M2M) applications.
"This new report demonstrates an extremely positive investment case for
LTE - Global Mobile Broadband", comments UMTS Forum Chairman Jean-
Pierre Bienaimé. "While it requires an upgrade of existing 3G infrastructures,
dramatically reduced opex costs compared with WCDMA and HSPA could see
operators break even as soon as 3-4 years after deploying LTE - Global
Mobile Broadband."
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L G V I E W T Y M O B I L E P H O N E E N A B L E S P L A Y B A C K V I D E O F R O M
T H E P C A N D T H E I N T E R N E T
LG and DivX announced their partnership to enable a high-quality consumer
media experience with the LG Viewty (Model: LG-KU990), a new 5.0 mega-
pixel digital camera phone available from LG Mobile.
The LG Viewty’s unprecedented multimedia capabilities reflect the extensive
partnership between LG Electronics and DivX. The LG Viewty enables
consumers to easily playback a wide range of DivX files from the PC on the
go or output to a TV monitor without converting to another format.
Consumers can also view DivX files from popular online video communities
such as Stage6.com at ten times the speed of WCDMA through the HSDPA
3.6 high speed internet access capability. DivX is a widely popular digital
media format that enables consumers to create, share and play back high-
quality video content across an ecosystem of platforms and devices.
The super sleek and stylish LG Viewty is the first in LG’s new line of high
technology handsets and boasts a number of ‘world first’ features never
seen before on a mobile handset, including 120 fps video recording as well
as unique camera functionality such as manual focus, image stabilizer and
handwriting recognition that makes editing easy on the Viewty’s 3-inch wide
LCD touch screen.
LG Viewty will go on sale from mid-October starting from Europe and on to
other regions
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V O D A F O N E N E V E R F A I L H I G H A V A I L A B I L I T Y S E R V I C E F O R
B L A C K B E R R Y
Europe : Vodafone UK announced
that it has completed a deal with
Neverfail, a leading global
software company providing
affordable continuous availability
and disaster recovery solutions.
Vodafone will now offer business
customers a high availability and
disaster recovery service for
mobile email using the Neverfail
software.
In today’s business environment
access to email whilst on the move is a key requirement for many
organizations.
Losing email access, even for a short time, can have drastic consequences
for businesses. The Vodafone Neverfail High Availability Service for
BlackBerry will provide uninterrupted availability of BlackBerry services to
Vodafone business customers.
The Vodafone Neverfail High Availability Service for BlackBerry monitors the health of the entire email environment, including the server hardware, the network infrastructure, the application and the operating system. If any anomalies are identified, Neverfail will immediately take action to prevent loss of service. It will either automatically attempt to restart applications before they fail, switch over to a secondary server, or alert the IT staff so that no downtime or loss of service is experienced. Once the issue is resolved, they are automatically switched back to the main servers and neither users nor administrators are required to restart their applications.
“As market leader in the UK in providing BlackBerry services, it was important to be able to offer robust access to email. By adding Neverfail’s solution into our Managed Service portfolio, we can offer enormous service expertise to protect critical parts of our customers’ IT infrastructure,” said Curt Hopkins, Head of Enterprise Mobility Solutions, Vodafone UK. “Neverfail has an enviable reputation for protecting mission-critical systems with its continuous availability solutions and we have selected them as our preferred provider for high availability and disaster recovery for BlackBerry and email implementations.”“Vodafone as a company relies on continuous mobile access to email and we have also selected the Neverfail solution to use within our own organization,” continued Hopkins. “Having complete confidence that email will be available 24/7 365 days a year is a significant advantage as many key staff depend on access via Blackberry devices in order to fulfil their roles.”“Vodafone is well ahead of the general telecommunications market. Rather than just providing handsets and airtime minutes, Vodafone is offering strategic services, such as high availability, to support the entire BlackBerry platform,” said Richard Ruddlesden, EMEA Channel Director, Neverfail. “We are very pleased that Vodafone has selected us to offer its customers an exceptional communications experience that is the best in the industry.”Vodafone Managed Services will work in partnership with Neverfail in the UK to offer customers advanced capabilities such as continuous availability for mobile devices and communications solutions from RIM, MicrosoftÒ and IBMÒ LotusÒ NotesÒ.
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