Re: The need of duplexer in low power operation

On Thu, Oct 11, 2012 at 9:58 AM, Sylvain Munaut 246tnt@gmail.com wrote:

Hi,

...

IIRC, both nanoBTS and SysmoBTS have separate antennas for Rx andTx and do not use duplexers. Do we need duplexer for UmTRXv2 if it operates in the low power mode, without an additional PA/LNA?

Note that both still have internal filters.

You mean bandpass filters? Are they only on Rx side or both Tx and Rx?

Antenna design also plays a role. The nanoBTS uses patch antenna separated by a lump of metal to minimize direct radiation from TX to RX.

Yes, I remember that nanoBTS has patch antennas for better isolation. But IIRC sysmoBTS has rubber duck antennas which made me wonder how do they do Tx/Rx isolation.