drivers/gps support ublox basic spectrum analyzer (UBX-MON-SPAN)

msg/CMakeLists.txt

@@ -156,6 +156,7 @@ set(msg_files
 	SensorCombined.msg
 	SensorCorrection.msg
 	SensorGnssRelative.msg
+	SensorGnssSpectrum.msg
 	SensorGps.msg
 	SensorGyro.msg
 	SensorGyroFft.msg

msg/SensorGnssSpectrum.msg

@@ -0,0 +1,16 @@
+# GNSS spectrum
+
+uint64 timestamp                  # time since system start (microseconds)
+uint64 timestamp_sample           # time since system start (microseconds)
+
+uint32 device_id                  # unique device ID for the sensor that does not change between power cycles
+
+# The center frequency at each bin: f(i) = center + span * (i - 127) / 256
+uint8[256] spectrum # dB Spectrum data (number of points = span/res)
+uint32 spectrum_span_hz    # Hz Spectrum span
+uint32 resolution_hz       # Hz Resolution of the spectrum
+uint32 center_frequency_hz # Hz Center of spectrum span
+
+uint8 programmable_gain_amplifier_db # dB Programmable gain amplifier
+
+uint8 ORB_QUEUE_LENGTH = 2