[Help] How to connect PA with LNA to share the same antenna!

Hi, everyone. I am design a 2.4GHz CMOS transceiver IC. But I don't know how to connect PA with LNA to share the same antenna, and has TX/RX switch. The PA core and LNA core are depicted as the figure below. Anybody can help me? Thanks!
guilinwxb


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You need a balun on each side (RX and TX), and the outputs of the baluns routed to the SPDT T/R switch.

use two spdt switches.
let say +ant, -ant is the common signal on state 1of swich it connects +ant to +PA and -ant to -PA on the switch toggle +ant to +LNA and -ANt to -LNA
You need tWO SPDT switches to have the required isolation.

Added after 36 seconds:

I mean DPDT should be OK

Hi

You can design the switch with 2 diodes!
of course you must consider the isolation.

Also you can use with cilculator and isolator!

David

Hi David,
Please let me know the realization of circulator or isolator in CMOS design

Thans everybody, after reference some IEEE paper, I decide to use this switch such as below and use a match network off chip. Tune the LC network to let the LNA's noise as low as possable and the output power of the PA is as large as possable. But I feel it's difficult to tune. Do you have any suggestion?

Thanks
guilinwxb
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I did not get the point of problem here. Please explain in detail.