I use two LimeSDR-USB (v1.4) as modems for data transfer. Modems operate in TDD mode. Tx and Rx modes change at approximately 380 Hz.
One antenna is used, connected through a switch. The switch provides approximately 30 dB of isolation between Tx and Rx.
When the power of its own Tx signal is low, everything works well. As the power of its own Tx signal increases, the Rx sensitivity decreases and the receiver malfunctions.
It is understood that this is due to intrinsic Tx power penetration into the Rx channel.
- Why does the intrusion of its own Tx signal into the Rx channel disrupt the operation of the modems if Tx and Rx operate at different time intervals (not simultaneously)? Is this a feature of the LMS7002?
- How to get rid of the influence of the own Tx signal on the Rx? It is clear that the problem can be solved by increasing the switch isolation between Tx and Rx to 100dB. Are there other ways?