Hello,
I want to use the LimeSDR as my modem to which I will connect my own RF module. This RF module has IQ signals as IOs and also performs direct up/downconversion.
According to the datasheet of the transceiver LMS7002M there are pins for the baseband IQ signals just after the DACs/ADCs ( e.g TXINI/TXINQ).
Is it possible to connect my module to these pins?
Short answer: No
Longer answer: If you look on github at page 4 of the schematic for the LimeSDR-USB and LimeSDR-Mini, or page 5 schematic for the LimeSDR-Micro under “Baseband external IO” none of those pins are accessible. This makes sense since pulling them out, unused, to an external interface would just be a source of additional noise injected into the baseband. So even though the pins exist on the LMS7002M chip they are not accessible on any of the current LimeSDR boards that I know about.
Hello mzs,
Thank you for your reply. Do you know if it is possible to order a custom board that can deliver access to the baseband IQ signals?