hi, the RSSI is used for known the signal strength if u r using any RF module like zigbee there is no need to design RSSI circuit /.its internal registers can find it.
Dear bvrkrishnaprasad :
Now I design the RSSI for RF loop , I must know the power level of RF Front end,then I use ADC to know the power level then control RF LNA , my LNA is digital control .
Dear bvrkrishnaprasad :
Now I design the RSSI for RF loop , I must know the power level of RF Front end,then I use ADC to know the power level then control RF LNA , my LNA is digital control .
what about you RF system structure? and what about your gain control mechanism? you know, in CDMA ystem, before the digital modulation, the signal level is constant, and the control gian is know (this information is from the calibration, the calibration data is stored in the memory), so the RSSI can received. then the RSSI can control the gain stage. for example, the LAN have four stage, the every stage LAN offset and the stage shift points you must decide , and then you calibrate the digital amplifier after ADC under every stage according to the input power, the result will store in the memory.
Dear Sir :
I know the RSSI is after LNA or Mixer, But how the gain theI decide ,
If the LNA is -20 ~50dB ,20dB per step . I don't know how to define the Gain of RSSI . Any comments ?