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NEXRAD Weather Radar
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In the United States, NEXt-generation weather RADars (NEXRAD) operate in the band 2700-3000 MHz. The radars are WSR-88D (Weather Surveillance Radar - 1988 Doppler) models. According to the National Weather Service, there are 160 operational NEXRAD radars throughout the U.S. and at some overseas locations.
According to NTIA technical report 13-490, the lowest tuned frequency for any NEXRAD is 2705 MHz, and the radars have the following technical characteristics:
| Peak transmitter power | 750 kW |
| Transmitter type | klystron tube |
| Operational frequency range | 2700-3000 MHz |
| Antenna type | 9 m (28 ft) diameter parabolic reflector with microwave feed horn at power center |
| Antenna gain | 45.5 dBi |
| Antenna height above ground | 24 m (80 ft) |
| Antenna beam width | 0.95 deg (3 dB width)
0.15 deg (boresight accuracy) |
| Antenna sidelobe levels | At least 27 dB below main-beam gain |
| Antenna beam scanning protocol | conical scan, +0.5 deg to +20 deg elevation |
| Antenna beam scanning rate | 6 rpm (10 sec/scan revolution interval) |
| Transmitted pulse widths | short pulse: 1.6 microsec
long Pulse: 4.5 microsec |
| Transmitted pulse modulation | P0N (unmodulated CW pulses) |
| Transmitted pulse repetition rates | short pulse: 318 to 1304 pulses/sec
long pulse: 318 to 452 pulses/sec |
| Receiver bandwidth | 0.795 MHz |
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Frequency Bands |
| Band | Use | Service11 | Table |
| 2700 - 3000 MHz | NEXRAD Weather Radar | Meteorological Aids | F |
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