- NEO-M8L-xxA – this is an automotive receiver, NEO-M8L-xxB – simplified, with a regular quartz generator instead of TCXO and in a regular version.
- NEO-M8P-0 – works only in rover and moving base mode, NEO-M8P-2 can be used in a stationary base mode as well.
- NEO-M8T has an additional antenna amplifier compared to LEA-M8T.
- NEO-M8Q (except NEO-M8Q-01A) and SAM-M8Q have an additional antenna amplifier and filter compared to MAX-M8Q.
- ZED-F9T-00B – this is L1/B1I/L2/E5b/B2I, while ZED-F9T-10B is L1/B1C/L5/E5a/B2a (without receiving L2 GLONASS), i.e. they require different antennas. LEA-F9T can work in both versions (L2 and L5), but not simultaneously, choosing either L2 or L5. In addition, there is a version of LEA-F9T-10B with an extended temperature range up to +105 degrees Celsius.
- F9P. A version of L1/L5 is planned, similar to ZED-F9T-10B.
Firmware updates
Receivers LEA-6T-1, M8F, M8T, M8N, M8J, M8L, M8P, M8U, M9L, M9N, M9V, F9P, F9H, F9R, F9T, F10T support firmware updates. Actual firmware updates can be downloaded from the u-blox website for M8L, M8U, M9N, M9L, M9V, F9P, F9H, F9R. For these receivers, it is recommended to check the firmware version, and if it is not the latest – update it.
Passive antennas and EMI protection
As described in the interference section, good protection from out-of-band interference requires two filters and a protective case around the receiver and high-frequency circuits. Any active antenna necessarily has both a filter (SAW) and an amplifier (LNA), so active antennas provide good protection in combination with a filter in the receiver or on the board.
All dual-frequency Ublox receivers (F9 and F10 series) can only be used with active antennas. Since these receivers have an internal antenna filter, they are protected from EMI.
All single-frequency Ublox receivers (series 6, 7, 8, M8, M9, and M10) can be used with both active and passive antennas.
Receivers 6T, M8F, NEO-M8T, M8N, NEO-M8Q, M8P, M9N, M9V, M10Q, M10S (as well as the less popular M8J) have additional antenna amplifiers and filters. These receivers are most protected from interference when working with active antennas. In addition, they can successfully work with passive antennas.
Receivers M8S, LEA-M8T contain only a filter. They are well protected from interference when working with active antennas, and to work with passive antennas, they need an additional amplifier on the board.
Receivers MAX-M8Q, M8L, M8U (as well as the less popular M8C, M8W, M8M, NEO-M8Q-01A, M9L, M10M) do not contain either an antenna amplifier or a filter. They can work with active antennas, and to work with passive antennas, they need a filter and an amplifier on the board.
Additionally, there are SAM and CAM family receivers with a built-in passive antenna. In these receivers, regardless of the model, there is an antenna filter and amplifier.
Signals and frequencies
Different receivers receive different signals. Frequencies and signals were described in the section L1, L2, L5, L3, AND SIMPLY L FREQUENCY BANDS
Let's repeat that the best signal is the newest one, which is currently Beidou-3 (B1C and B2A), and the worst one is the oldest one, which is GLONASS.
- 6T: GPS/QZSS/SBAS L1 (1575.420 MHz)
- 8Q, 8M, 8C: GPS/QZSS/SBAS L1 (1575.420 MHz), GLONASS G1 (1598.062-1605.375 MHz), only 1 system at a time. GPS is naturally better than GLONASS.
M8P:
- GPS/QZSS/SBAS L1 (1575.420 MHz),
- GLONASS G1 (1598.062-1605.375 MHz),
- BEIDOU B1I (1561.098 MHz), only 2 systems at a time.
If there are corresponding RTK corrections, GPS + BEIDOU is recommended. But keep in mind that the RTK method requires an exact match of base and rover signals, so the corrections must be B1I, and B1 corrections can mean either B1I or B1C. If there are no B1I corrections, then traditionally, GPS and GLONASS.
M8F:
- GPS/QZSS/SBAS L1 (1575.420 MHz),
- GLONASS G1 (1598.062-1605.375 MHz),
- EIDOU B1I (1561.098 MHz), only 2 systems at a time.
For greater accuracy, GPS+BEIDOU is better. As for spoofing... script kiddies usually can spoof only GPS, so for anti-spoofing, GLONASS+BEIDOU is better.
M8S, M8C, M8Q, M8W, M8T, M8J, M8M, M8N, M8L, M8U:
- GPS/QZSS/SBAS L1 (1575.420 MHz),
- GLONASS G1 (1598.062-1605.375 MHz),
- GALILEO E1 (1575.420 MHz),
- BEIDOU B1I (1561.098 MHz) – only 3 systems at a time.
It is best to abandon GLONASS and use GPS + GALILEO + BEIDOU. However, if spoofing is expected, it is better to reject GPS since most spoofers can only spoof it.
M9L, M9N, M9V:
- GPS/QZSS/SBAS L1 (1575.420 MHz),
- GLONASS G1 (1598.062-1605.375 MHz),
- GALILEO E1 (1575.420 MHz),
- BEIDOU B1I (1561.098 MHz) – all 4 systems simultaneously.
M10M, M10S:
- GPS/QZSS/SBAS L1 (1575.420 MHz),
- GLONASS G1 (1598.062-1605.375 MHz),
- GALILEO E1 (1575.420 MHz),
- BEIDOU B1I (1561.098 MHz) / B1C (1575.420 MHz) – all 4 systems simultaneously.
M10Q:
- GPS/QZSS/SBAS L1 (1575.420 MHz),
- GLONASS G1 (1598.062-1605.375 MHz),
- GALILEO E1 (1575.420 MHz),
- BEIDOU B1C (1575.420 MHz) – all 4 systems simultaneously.
- For M9/M10, it is better to use all systems. However, if spoofing is expected, it is better to reject GPS, as most spoofers can only spoof it. As for choosing between B1I and B1C, B1C is more accurate, and there are 1.5 times more satellites with B1I. So, for solution availability in urban canyons, B1I is better, while for accuracy, B1C is preferred.
F9P, F9H, F9R:
- GPS/QZSS/SBAS L1 (1575.420 MHz) / L2 (1227.600 MHz),
- GLONASS G1 (1598.062-1605.375 MHz) / G2 (1242.937-1248.625 MHz),
- GALILEO E1 (1575.420 MHz) / E5B (1207.140 MHz),
- BEIDOU B1I (1561.098 MHz) / B2I (1207.140 MHz) - dual-frequency L1/L2/E5B, nothing to choose here
ZED-F9T-00B:
- GPS/QZSS/SBAS L1 (1575.420 MHz) / L2 (1227.600 MHz),
- GLONASS G1 (1598.062-1605.375 MHz) / G2 (1242.937-1248.625 MHz),
- GALILEO E1 (1575.420 MHz) / E5B (1207.140 MHz),
- BEIDOU B1I (1561.098 MHz) / B1C (1575.420 MHz) / B2I (1207.140 MHz) – dual-frequency L1/L2/E5B, better to use B1C for higher accuracy
ZED-F9T-10B:
- GPS/QZSS/SBAS L1 (1575.420 MHz) / L5C (1176.450 MHz),
- NavIC L5 (1176.450 MHz),
- GLONASS G1 (1598.062-1605.375 MHz),
- GALILEO E1 (1575.420 MHz) / E5A (1176.450 MHz),
- BEIDOU B1I (1561.098 MHz) / B1C (1575.420 MHz) / B2A (1176.450 MHz) – dual-frequency L1/L5, better to use B1C for higher accuracy and disable GLONASS entirely (since it is only on one frequency here, it does more harm than good to the solution).
LEA-F9T: dual-mode. Can be used as both ZED-F9T-00B (L1/L2/E5B) and ZED-F9T-10B (L1/L5). Strongly recommended to use the L1/L5 option due to its higher accuracy.
F10T:
- GPS/QZSS/SBAS L1 (1575.420 MHz) / L5C (1176.450 MHz),
- NavIC L5 (1176.450 MHz),
- GLONASS G1 (1598.062-1605.375 MHz),
- GALILEO E1 (1575.420 MHz) / E5A (1176.450 MHz),
- BEIDOU B1C (1575.420 MHz) / B2A (1176.450 MHz) – dual-frequency L1/L5, nothing to choose here
- As previously described in the L2 or L5 section, some tricks are required to receive GPS L5C. For the ZED-F9T-10B, LEA-F9T, and F10T receivers, this is described in the following application note: GPS L5 configuration
© Eltehs SIA 2023
