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It's a very different architecture. The original LimeSDR was able to receive from 100kHz - 3.8GHz. The LimeSDR Mini can only do 10MHz - 3.5GHz. It also only sup

It's a very different architecture. The original LimeSDR was able to receive from 100kHz - 3.8GHz. The LimeSDR Mini can only do 10MHz - 3.5GHz. It also only supports about 1/2 the bandwidth and sample rate. The official page highlights more differences: https://www.crowdsupply.com/lime-micro/limesdr-mini https://www.crowdsupply.com/lime-micro/limesdr-mini

stagger87 9y ago
Both devices use the same transceiver chip so I don't think the architecture is very different at all.
- simcop2387 9y ago
  Same transciever, different FPGA, different ADCs, no extra ram, and some other differences. Different architectures on the digital sides of things.
ChuckMcM 9y ago
The original LimeSDR was able to receive from 100kHz - 3.8GHz. This is incorrect, and it is the source of much pain. The chip that provides the ADCs and DACs, the LMS7002, has an input range of 100kHZ to 3.8Ghz but the design of the LimeSDR front end filter banks made its minimum usable frequency with decent SNR about 200Mhz[1]. Initially you couldn't even pass a tuning frequency below that through the API. Even with the vendor/factory supplied "fix" the LimeSDR has a hard time getting below 100Mhz. A lot of people read the chip spec and expected the card implementation to be able to do the same, they were unpleasantly surprised to find out that was not the case. Hence a lot of griping early on. On the plus side, since it was deaf to the FM band it was more sensitive to higher frequency signals. Other SDRs like the SDRPlay RSP2[2] are actually quite usable down even into the AM range (500Khz - 2Mhz) and have a notch filter for the FM band to keep it from swamping the input and eating up all the dynamic range. [1] Firstly, we would like to highlight the fact that it is not possible to achieve optimum performance across the entire operating range of LimeSDR — all the way from 100kHz to 3.8GHz — with only a single matching network. -- https://myriadrf.org/blog/optimising-limesdr-matching-hf/ https://myriadrf.org/blog/optimising-limesdr-matching-hf/ [2] https://www.sdrplay.com/rsp2/ https://www.sdrplay.com/rsp2/
- simcop2387 9y ago
  Interesting I wasn't aware of the filter issue with the original LimeSDR. The lower range was one reason why it was on the top of my list of something to pick up for when I've got a proper reason to need a full featured SDR, rather than just the mostly toy RTLSDR based stuff. That said I think it's still up there for the high input bandwidth (60MHz woo!) for me. Unlikely to ever need real transmit ability but being able to receive that much is a nice feature.
  - ChuckMcM 9y ago
    Agreed, the bandwidth is nice, but most of the signals you would play with in the lower bands have much lower bandwidth. Digital TV (like DVB_T) for example is only about 8Mhz. Generally in the lower frequencies taking up more than a few megahertz of bandwidth really messes with the available spectrum. Up in the microwave region (2Ghz+) that is not as much of a concern.

stagger87 9y ago

Both devices use the same transceiver chip so I don't think the architecture is very different at all.

simcop2387 9y ago
Same transciever, different FPGA, different ADCs, no extra ram, and some other differences. Different architectures on the digital sides of things.

ChuckMcM 9y ago

The original LimeSDR was able to receive from 100kHz - 3.8GHz. This is incorrect, and it is the source of much pain. The chip that provides the ADCs and DACs, the LMS7002, has an input range of 100kHZ to 3.8Ghz but the design of the LimeSDR front end filter banks made its minimum usable frequency with decent SNR about 200Mhz[1]. Initially you couldn't even pass a tuning frequency below that through the API. Even with the vendor/factory supplied "fix" the LimeSDR has a hard time getting below 100Mhz. A lot of people read the chip spec and expected the card implementation to be able to do the same, they were unpleasantly surprised to find out that was not the case. Hence a lot of griping early on. On the plus side, since it was deaf to the FM band it was more sensitive to higher frequency signals. Other SDRs like the SDRPlay RSP2[2] are actually quite usable down even into the AM range (500Khz - 2Mhz) and have a notch filter for the FM band to keep it from swamping the input and eating up all the dynamic range. [1] Firstly, we would like to highlight the fact that it is not possible to achieve optimum performance across the entire operating range of LimeSDR — all the way from 100kHz to 3.8GHz — with only a single matching network. -- https://myriadrf.org/blog/optimising-limesdr-matching-hf/ https://myriadrf.org/blog/optimising-limesdr-matching-hf/ [2] https://www.sdrplay.com/rsp2/ https://www.sdrplay.com/rsp2/

simcop2387 9y ago
Interesting I wasn't aware of the filter issue with the original LimeSDR. The lower range was one reason why it was on the top of my list of something to pick up for when I've got a proper reason to need a full featured SDR, rather than just the mostly toy RTLSDR based stuff. That said I think it's still up there for the high input bandwidth (60MHz woo!) for me. Unlikely to ever need real transmit ability but being able to receive that much is a nice feature.
- ChuckMcM 9y ago
  Agreed, the bandwidth is nice, but most of the signals you would play with in the lower bands have much lower bandwidth. Digital TV (like DVB_T) for example is only about 8Mhz. Generally in the lower frequencies taking up more than a few megahertz of bandwidth really messes with the available spectrum. Up in the microwave region (2Ghz+) that is not as much of a concern.