Our customer is going to use ADF5901 for their design however they need some clarification regarding the correct operation of two Tx channels.
In some earlier questions it was mentioned that: "In many cases only one Tx is used, but 2 Tx's are used for MIMO operation where the Tx's are alternatively switched ON/OFF to give virtual Rx channel and more system performance. "
But there are some additional questions:
1) Alternative switching of the two channels means their alternate use (i.e. alternatively one is ON - then the second), or joint too (each can be on or off, i.e. both can be switched on simultaneously)?
2) According to the documentation, both channels are implemented in parallel, i.e. data in them can not differ. But if there is a link to MIMO, then there should be two independent transmitting channels with independent data. Or that is wrong?
3) Probably it is possible to connect these two channels to two antennas and thereby implement alternate changes in the type of polarization or direction of transmission. Then, indeed, they cannot work at the same time. The whole point is to switch. But there is still no talk of MIMO, since the bandwidth does not increase in this way.
Could you please clarify in detail?
Also there other question:
- What is a minimum duration of FMCW signal in ADF4159 with a bandwidth of 100MHz and more?
Thanks in advance and look forward to your reply.