Spectrum Summary of Spectrum Summary of GBT Receiver BandsGBT Receiver Bands

Caveat Emptor:Many of these scans are old by as much as several years. Since there is no systematic archiving of GBT RFI scans, reporting is spotty, and an overview like this is difficult to piece together. Automated, archival monitoring of the RFI environment at Green Bank is one of the goals of our group.

PF1.1: 290 MHz – 395 MHzPF1.1: 290 MHz – 395 MHz

Military Aircraft (225 MHz – 400 MHz) Evers MOA and others

Leaky Local Cable TV, Part 15 devices, unintentional sources

PF1.1: 290 MHz – 395 MHz PF1.1: 290 MHz – 395 MHz (cont’d)(cont’d)

Cable TV Video Carrier Audio CarrierChannel (MHz) (MHz)

26 235.25 239.7527 241.25 245.7528 247.25 251.7529 253.25 257.7530 259.25 263.7531 265.25 269.7532 271.25 275.7533 277.25 281.7534 283.25 287.7535 289.25 293.7536 295.25 299.7537 301.25 305.7538 307.25 311.7539 313.25 317.7540 319.25 323.7541 325.25 329.7542 331.25 335.7543 337.25 341.7544 343.25 347.7545 349.25 353.7546 355.25 359.7547 361.25 365.7548 367.25 371.7549 373.25 377.7550 379.25 383.7551 385.25 389.7552 391.25 395.7553 397.25 401.7554 403.25 407.75

PF1.2: 385 MHz – 520 MHzPF1.2: 385 MHz – 520 MHz

Military aircraft

PF1.3: 510 MHz – 690 MHzPF1.3: 510 MHz – 690 MHz

Spectrum dominated by UHF TV stations located outside NRQZ. Only Channel 37 (608 MHz - 614 MHz) really usable. The impending shift to digital broadcasting will only worsen the picture.

Digital Channels

RA Band

PF1.4: 680 MHz – 920 MHzPF1.4: 680 MHz – 920 MHz

UHF TV

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Land Mobile Airphone Services

Radiolocation

902-928 ISM band Intentional Radiators

PF2: 910 MHz – 1230 MHzPF2: 910 MHz – 1230 MHz

Radiolocation/ISM

Aeronautical Radionavigation (mobile and land based)

Fixed/Mobile (various)

L Band: 1150 MHz – 1730 MHzL Band: 1150 MHz – 1730 MHz

GEOS or NOAA WX ?IRIDIUM: 1621 - 1627GPS L1: 1575.42 L2: 1227.6 L3: 1381.05Aeronautical Radionavigation

Notch Filter designed to keep radar at Roanoke Airport from overloading receiver.

S Band: 1730 MHz – 2600 MHzS Band: 1730 MHz – 2600 MHz

All Az, filtered, 2/8/02

2400 – 2483.5 ISM band Unlicensed Intentional Radiators

2320 – 2360 Sirus and XM Broadcast Satellites

S Band: 200 mW WIFI Potential S Band: 200 mW WIFI Potential Interference MapInterference Map

Above S BandAbove S Band

Generally, less terrestrial sources and more satellite and airborne sources. A few possibilities:

• 3700-4200 MHz: geostationary satellite TV downlinks• 5725-5850 MHz: ISM band Unlicensed Intentional

Radiators• 11.7-12.7 GHz: geostationary satellite TV downlinks