RFI at S-Band (2-4 GHz)
| Frequency (MHz) | Description | Origin | Classification | Spectrum |
|---|---|---|---|---|
| 2178.0-2195.0 | ?? | Intermittent | plot | |
| 2106.4 | High alt baloon | NM, FT Sunmer | Intermittent | plot |
| 2204.5 | Test telemetry | NM, FT Bliss | Intermittent | plot |
| 2180-2290 | Satellite downlink | OHD?GSO/MEO | Continuous | plot |
| 2227.5-2231.5 | ?? | NM, WSMR? | Intermittent | plot |
| 2246.5-2252.5 | ?? | NM, WSMR? | Intermittent | plot |
| 2268.5-2274.5 | ?? | NM, WSMR? | Intermittent | |
| 2282.5-2288.5 | ?? | NM, WSMR? | Intermittent | |
| 2314.5-2320.5 | ?? | NM, WSMR? | Intermittent | |
| 2320.0-2332.5 | Sirius DARS | OHD/GSO-Tundra | Continous | plot |
| 2324.5-2330.5 | ?? | NM, WSMR? | Intermittent | |
| 2332.5-2345.0 | XM DARS | OHD/GSO-Equatoral | Continuous | plot |
| 2334.5-2340.5 | ?? | NM, WSMR? | Intermittent | |
| 2387.5 | High alt baloon | NM, FT Sunmer | Intermittent | |
| 2400.0-2483.5 | Microwave Ovens | Everywhere | Intermittent | plot |
| 2400.0-2483.5 | WiFi(802.11b) Wireless | Everywhere | Intermittent | plot |
| 2411.0-2413.0 | Hughes Net WiFi | Ranch houses | Continuous | |
| 2483.5-2500.0 | GlobalStar downlink | Everywhere | Continuous | |
| 2741 | ABQ NEXRAD1 | ABQ | Intermittent | |
| 2791 | ABQ NEXRAD1 | ABQ | Intermittent | |
| 3700.0-4200.0 | Satellite downlinks | OHD | Continuous | plot1, plot2, plot3 |
The Sirius digital radio system (and probably the satellites in the 2178 -- 2195 MHz band) comprises three satellites in a 24-hour, high eccentricity orbit with the apogee above the central U.S. For the Sirius system, the orbit is arranged such that each of the three satellites spends about eight hours near an azimuth of 25 degrees and an elevation of 65 degrees. The corresponding region in astronomical coordinates is between declinations 50 to 65 degrees, and hour angles between -1 and -2 hours. Observations at S-band within that area may -- or may not -- be seriously affected. The most reliable way to judge the seriousness of the satellite emissions is to inspect the switched power table data, particularly in those subbands where there is little RFI.
