By Kip Smith

RADIOWAVES IN AGRICULTURE

THEORY OF OPERATION

• Radiowaves travel at the speed of light.

• It is part of the electromagnetic spectrum.

• Waves are measured in two ways, wavelength and frequency.

TRANSMITTERS• An Electronic device which, with the aid of an antenna, produces radio waves.

• Radio Frequency Alternating Current

• Transmitters consist of 5 things

• Power Supply

• Electronic Oscillator

• Modulator

• Power Amplifier

• Tuner

RECIEVERS• A device that receives radiowaves and converts the information to a more usable form.

• A preamplifier processes the “noise” and sends it to the amplifier. The amplifieradds power to boost the signal.

COMMONLY KNOWN FREQUENCIES• Radio Frequencies exsist from exactly 3 khz to 300,000,000 khz (or 300 Ghz)

Communication Style Frequency

Human voice 75-300 hz

AM Radio 535-1605 khz

CB Radio 26.95-27.405 Mhz

Television (Channels 2 -6) 54-72 & 76-87 Mhz

FM Radio 87.5-108.0 Mhz

Verizon iPhone 900 Mhz or 1800 Mhz

GPS Navigation 1.2276 and 1.575 Ghz

Broadcasting Satellites 12.2-12.7 Ghz

ELECTROMAGNETIC SPECTRUM

GLOBAL POSITIONING

• Uses Bands L1 and L2 (1575.42 MHz) and (1227.60 MHz)

• The Clinton Administration opened up GPS signals to the public in 1998.

• We are currently using GPSII technology. GPSIII technology will be launched into space starting in 2014.

WAAS (WIDE AREA AUGMENTATION SYSTEM) &RTK (REAL TIME KINETICS)

It was only required to provide an accuracy of up to 25 ft. but researchers were surprised to find accuracy of 3 to 4 ft.

Consists of three parts:

• Ground Segment

• Space Segment

• User Segment

RTK uses mobile base stations as well as Ground stations to achieve greater accuracy.

The Mobile Station uses a Joey Radio Modem to transfer position to the cab.

JDLINK AND CASE AFS CONNECTAKA “TELEMATICS”

• Ability to track and gain information from vehicles in or away from the field.

• Gain additional technology support from trained technicians 24/7.

• Track farm equipment.

MACHINESYNC

DISPLAY SYNC• Ability to transfer data wirelessly (guidance lines, application rates, population, and test

weight)

• Creates faster information sharing

• Ability to share data BETWEEN displays.

DISPLAY SYNC

SUMMARY

• Radiowaves are all around us

• It takes a minute frequency to broadcast GPS to the entire country

• WAAS is a corrected signal, but corrected with minimal accuracy.

• RTK requires two types of corrections

• John Deere and Case are both looking towards information transferred through radiowaves

QUESTIONS?