Max Bandwidth of Dual RX

Projects LimeSDR
7

I assume you are interesting in RX data only. Then there are a few things to consider:

  1. Maximum USB3 data throughput from LimeSDR-USB to PC. Maximum theoretical data throughput in this case is 400MB/s (32 bit interface between USB MCU (FX3) and FPGA running @ 100MHz). Real number we were to achieve with LimeSDR-USB is 387MB/s.
  2. Maximum RF bandwidth of LMS7002M analog frontend. Theoretically it is limited by ADC sample rate (while filters in the analogue frontend may be bypassed) which is 160MHz. Hence theoretical RF bandwidth is 160MHz. Although in a real life application I would expect RF bandwidth to be 120MHz (as mentioned by Andrew) @ 160MHz sample rate.
  3. If we are using MIMO, then RX will produce 4 * 160 = 640MS/s which is 640 * 1.5 = 960MB/s, while one sample is 12 bit. As you can see from item (1) above there is no way to transfer such an amount of data to the PC.
  4. If we set ADC sample rate to 61.44MHz, then data throughput (using the math from item (3)) will be 368.64MB/s, which is doable. Hence you have 61.44MHz RF bandwidth per each MIMO channel transferred to the PC.
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