Interference Calculator

Using Definitions for calculator:

GNSS

GNSS (Global Navigation Satellite System) is a satellite system that is used to pinpoint the geographic location of a user’s receiver anywhere in the world. Two GNSS systems are currently in operation: the United States’ Global Positioning System (GPS) and the Russian Federation’s Global Orbiting Navigation Satellite System (GLONASS). A third, Europe’s Galileo, is slated to reach full operational capacity in 2008. Each of the GNSS systems employs a constellation of orbiting satellites working in conjunction with a network of ground stations.

Satellite-based navigation systems use a version of triangulation to locate the user, through calculations involving information from a number of satellites. Each satellite transmits coded signals at precise intervals. The receiver converts signal information into position, velocity, and time estimates. Using this information, any receiver on or near the earth’s surface can calculate the exact position of the transmitting satellite and the distance (from the transmission time delay) between it and the receiver. Coordinating current signal data from four or more satellites enables the receiver to determine its position.

Depending on the particular technologies used, GNSS precision varies. For example, the United States Department of Defense originally used an intentional degradation (known as “Selective Availability,” or “SA”) of GPS signals to prevent potential military adversaries from using the positioning data. Because of SA, GPS accuracy was limited to a 100-meter range for civilian users, although military equipment enabled accuracy to within a single meter. In May 2000, a presidential order mandated that SA be discontinued. Without SA, all GPS receivers are potentially accurate to within 15 meters. When available, Galileo will provide position accuracy to within one meter.

F1 F2

All frequencies are entered and displayed in megahertz (MHz).

Enter F1 and F2 as difference center frequencies in MHz to yield their mixing products as a result of second and third order harmonics – no attempt is made to assess signal levels, just “beat frequency” products. Re-enter new values of F1 and F2 to repeat the calculations to assess a new set of F1 and F2 mixing products.

The spreadsheet determines if any of the second and third order “beat” products result in a spurious signal that lands in one of the GNSS location based service (LBS) system receiver passband frequencies. When a calculated “beat” product is determined by “fx” function to have landed within a specific GNSS system passband, the cell next to the “Interferer” box displays the function that results in the creation of a potential interferer. Good hunting!

Interferers

F1 F2 Interferer Details: Affected GNSS Service(s): F1, F2 Sources:
1712.7 1850 2F1-F2 = 1575.4 USA L1, L1C, E1 3GPP Band 3 UL + GSM1850
2417 1850 2F2-F1 = 1283 E6, L2C, B2 WLAN Ch 2 + GSM1850
2422 1850 2F2-F1 = 1278 E6, L2C, B2 WLAN Ch 3 + GSM1850
2427 1850 2F2-F1 = 1273 E6, L2C, B2 WLAN Ch 4 + GSM1850
2432 1850 2F2-F1 = 1268 E6, L2C, B2 WLAN Ch 5 + GSM1850
2437 1850 2F2-F1 = 1263 E6, L2C, B2 WLAN Ch 6 + GSM1850
2442 1850 2F2-F1 = 1258 E6, L2C, B2 WLAN Ch 7 + GSM1850
2447 1850 2F2-F1 = 1253 E6, L2C, B2 WLAN Ch 8 + GSM1850
2452 1850 2F2-F1 = 1248 E6, L2C, B2 WLAN Ch 9 + GSM1850
2457 1850 2F2-F1 = 1243 E6, L2C, B2 WLAN Ch 10 + GSM1850
2462 1850 2F2-F1 = 1238 E6, L2C, B2 WLAN Ch 11 + GSM1850
2467 1850 2F2-F1 = 1233 E6, L2C, B2 WLAN Ch 12 + GSM1850
2472 1850 2F2-F1 = 1228 E6, L2C, B2 WLAN Ch 13 + GSM1850
2412 1807.4 2F2-F1 = 1202.8 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 1 + Band 3 DL (1807.4 to 1812.4)
2412 1812.4 2F2-F1 = 1212.8 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 1 + Band 3 DL (1807.4 to 1812.4)
2412 1816.6 2F2-F1 = 1221.2 E6, L2C, B2 WLAN Ch 1 + Band 3 DL (1816.6 to 1847.8)
2412 1847.8 2F2-F1 = 1283.6 E6, L2C, B2 WLAN Ch 1 + Band 3 DL (1816.6 to 1847.8)
2437 1807.4 2F2-F1 = 1177.8 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 6 + Band 3 (1807.4 to 1824.8)
2437 1824.8 2F2-F1 = 1212.6 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 6 + Band 3 (1807.4 to 1824.8)
2437 1829.2 2F2-F1 = 1221.4 E6, L2C, B2 WLAN Ch 6 + Band 3 (1829.2 to 1860.4)
2437 1860.4 2F2-F1 = 1283.8 E6, L2C, B2 WLAN Ch 6 + Band 3 (1829.2 to 1860.4)
2437 1838.6 2F2-F1 = 1240.2 GLONASS L2C WLAN Ch 6 + Band 3 (1838.6 to 1844.4)
2437 1844.4 2F2-F1 = 1251.8 GLONASS L2C WLAN Ch 6 + Band 3 (1838.6 to 1844.4)
2422 1807.4 2F2-F1 = 1172.8 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 3 to Ch 7 + Band 3 (1807.4 to 1827.4 MHz)
2442 1827.4 2F2-F1 = 1212.8 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 3 to Ch 7 + Band 3 (1807.4 to 1827.4 MHz)
2422 1831.6 2F2-F1 = 1221.2 E6, L2C, B2 WLAN Ch 3 + Band 3 (1831.6 to 1862.8)
2422 1862.8 2F2-F1 = 1283.6 E6, L2C, B2 WLAN Ch 3 + Band 3 (1831.6 to 1862.8)
2472 1821.2 2F2-F1 = 1170.4 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 13 + Band 3 (1821.2 to 1842.4 MHz)
2472 1842.4 2F2-F1 = 1212.8 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 13 + Band 3 (1821.2 to 1842.4 MHz)
2472 1846.6 2F2-F1 = 1221.2 E6, L2C, B2 WLAN Ch 13 + Band 3 (1846.6 to 1877.6 MHz)
2472 1877.6 2F2-F1 = 1283.2 E6, L2C, B2 WLAN Ch 13 + Band 3 (1846.6 to 1877.6 MHz)
2472 871.4 F1-F2 = 1600.6 GLONASS L1 WLAN Ch 13 + Band 5 (871.4 to 875.8 MHz)
2472 875.8 F1-F2 = 1596.2 GLONASS L1 WLAN Ch 13 + Band 5 (871.4 to 875.8 MHz)
2437 1807.4 2F2-F1 = 1177.8 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 6 + Band 3 (1807.4 to 1824.8 MHz)
2437 1824.8 2F2-F1 = 1212.6 L5, E5A, E5B, ALTBOC, B3 WLAN Ch 6 + Band 3 (1807.4 to 1824.8 MHz)
2437 1838.6 2F2-F1 = 1240.2 GLONASS L2C WLAN Ch 6 + Band 3 (1838.6 to 1844.4 MHz)
2437 1844.4 2F2-F1 = 1251.8 GLONASS L2C WLAN Ch 6 + Band 3 (1838.6 to 1844.4 MHz)
2437 1829.2 2F2-F1 = 1221.4 E6, L2C, B2 WLAN Ch 6 + Band 3 (1829.2 to 1860.4 MHz)
2437 1860.4 2F2-F1 = 1283.8 E6, L2C, B2 WLAN Ch 6 + Band 3 (1829.2 to 1860.4 MHz)
1870.2 700 F1-F2 = 1170.2 L5, E5A, E5B, ALTBOC, B3 Band 3 (1870.2 to 1877.4 MHz) + TVWS or LTE
1877.4 700 F1-F2 = 1177.4 L5, E5A, E5B, ALTBOC, B3 Band 3 (1870.2 to 1877.4 MHz) + TVWS or LTE
5180 3800 2F2-F1 = 2420 WiFi Channels 1 to 4 WiFi Channel 36 + LTE-A Ch 43
5180 3600 F1-F2 = 1580 L1-L1C-E1-B1 WiFi Channel 36 + LTE-A Ch 43
5200 3600 F1-F2 = 1600 GLONASS L1 WiFi Channel 40 + LTE-A Ch 43
5620 3600 F1-F2 = 1580 L1-L1C-E1-B1 WiFi Channel 124 + LTE-A Ch 43

GNSS Systems Today

Navigation Standard RF Carrier Frequency, Fc (MHz) Fundamental Frequency, Fo (MHz) TypicalcBest Case Receiver Sensitivity Level for C/A*c(dBm) Typical Best Case Receiver Sensitivity Level for P-code*(dBm) Typical Worst Case Receiver Sensitivity Level (dBm)
USA GPS L1 1575.42 10.23 -110 to -130 -113 to -133 -163
USA GPS L1C 1575.42 10.23 -108 to -128 -111 to -131 -161
USA GPS L2C 1227.6 10.23 -108 to -128 -111 to -131 -161
USA GPS L5 1176.45 10.23 -105 to -125 -108 to -128 -158
Russia GLONASS L1 1602.000 10.23 -111 to -131^ -114 to -134 -164
Russia GLONASS L2 1246.000 10.23 -117 to -137^ -120 to -140 -170
EU/Canada Galileo E1 1575.42 10.23 -107 to -127** -110 to -130 -160
EU/Canada Galileo E5A 1176.45 10.23 -105 to -125** -108 to -128 -158
EU/Canada Galileo E5B 1207.14 10.23 -105 to -125** -108 to -128 -158
EU/Canada Galileo ALTBOC 1191.795 10.23 -105 to -125** -108 to -128 -158
EU/Canada Galileo E6 1278.75 10.23 -105 to -125** -108 to -128 -158
PRC COMPASS/Beidou-2 B1 1561.098 1.023 -114 to -134^^ -117 to -137 -167
PRC COMPASS/Beidou-2 B2 1268.52

1278.75

10.23

10.23

-114 to -134 -117 to -137 -167
PRC COMPASS/Beidou-2 B3 1207.14 10.23 -114 to -134 -117 to -137 -167
©2016. Parsec Technologies Inc. ALL RIGHTS RESERVED. This spreadsheet is the property of Parsec Technologies, Inc. (“Parsec”), http://parsec-t.com, and is protected by USA Copyright laws. Its use is authorized to individuals requiring the means to assess the mixing products occurring when two fundamental tones of known frequency are in operation in close proximity to each other (also known as “cohabitation”). Contact techsupport@parsec-t.com, with any questions related to the use, operation, and function of this spreadsheet calculator or to make suggestions for improvement.