3 ms·
> reading signals -30db below noise level Can you tell us a little more about this?
by AsymetricCom 13y ago
> reading signals -30db below noise level
Can you tell us a little more about this?
- TeMPOraL 13y agoThe thermal noise level for 2MHz (GPS freq) is around -111dBm [0] and typical GPS signals on Earth surface are around -130 to -160dBm [1] [2]. There was a discussion here about GPS jamming recently, and some commenters also talked about it [3] [4]. [0] - http://en.wikipedia.org/wiki/Johnson%E2%80%93Nyquist_noise#Noise_power_in_decibels http://en.wikipedia.org/wiki/Johnson%E2%80%93Nyquist_noise#N... [1] - http://en.wikipedia.org/wiki/DBm http://en.wikipedia.org/wiki/DBm [2] - http://www.gpsinformation.net/main/gpspower.htm http://www.gpsinformation.net/main/gpspower.htm [3] - https://news.ycombinator.com/item?id=6124811 https://news.ycombinator.com/item?id=6124811 [4] - https://news.ycombinator.com/item?id=6124965 https://news.ycombinator.com/item?id=6124965
- AsymetricCom 13y agoMore specifically, I was wondering what the algorithm would be for such a feat. One of the yc comments has a layman description linked from wikipedia http://en.wikipedia.org/wiki/GPS_signals#Demodulation_and_decoding http://en.wikipedia.org/wiki/GPS_signals#Demodulation_and_de...