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Newbie level 4
What exactly are BP Amp and AmpI/AmpQ values? (SIMCom GPS)
Hello,
I have a question regarding GPS antenna (at least I think it's about the antenna). While checking out GPS features (like TTFF and GPS accuracy) of my SIMCom 3G & GPS EVB kit I've noticed this AmpI/AmpQ term which is a part of GPS fix. Typical fix info (copy-pasted from SIMCom documentation) that one can get on a serial port would be something like this :
+CGPSINFO:3113.343286,N,12121.234064,E,250311,072809.3,44.1,0.0,0
AmpI/AmpQ: 420/421
My question is, what exactly is this AmpI/AmpQ? What are I and Q? SIMCom documentation gives no explanation. All I can tell is that this value depends a lot on GPS antenna's positioning & environment and that also it differs from one antenna to another (I've tried 3 different GPS antennas). Typical values of AmpI/AmpQ that I'm getting are in a range from, say, 380/370 to 640/640, depends on the antenna's position. Googling didn't help a lot either, all I could have found so far is that this AmpI/AmpQ value might have something to do with BP Amp and noise input level to ADC.
Any help would be much appreciated.
Hello,
I have a question regarding GPS antenna (at least I think it's about the antenna). While checking out GPS features (like TTFF and GPS accuracy) of my SIMCom 3G & GPS EVB kit I've noticed this AmpI/AmpQ term which is a part of GPS fix. Typical fix info (copy-pasted from SIMCom documentation) that one can get on a serial port would be something like this :
+CGPSINFO:3113.343286,N,12121.234064,E,250311,072809.3,44.1,0.0,0
AmpI/AmpQ: 420/421
My question is, what exactly is this AmpI/AmpQ? What are I and Q? SIMCom documentation gives no explanation. All I can tell is that this value depends a lot on GPS antenna's positioning & environment and that also it differs from one antenna to another (I've tried 3 different GPS antennas). Typical values of AmpI/AmpQ that I'm getting are in a range from, say, 380/370 to 640/640, depends on the antenna's position. Googling didn't help a lot either, all I could have found so far is that this AmpI/AmpQ value might have something to do with BP Amp and noise input level to ADC.
Any help would be much appreciated.
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