On Thu, May 14, 2009 at 6:01 AM, <karda...@telecom.tuc.gr> wrote: > I use USRP 1 and RFX2400..I try to find if the amplifier of the transmitter > has > a non-linear region. Do you know anything about this topic? Is there a > non-linear region that i could find? I try to find a relation of P_in versus > P_out at the amplifier of the transmitter. > > If there is only linear region, please tell me...
The RFX2400 (and other RFX boards) begin to go into nonlinearity at about 20 dB below its maximum output power, though this is a rough approximation and varies board-to-board. In practice, you can stay in the linear region by ensuring the amplitude of your TX signal stays below 0.1 or so (when using USRP2), or below 3000 (when using USRP1). If making this precise is important to you, you can perform a two-tone test using usrp_siggen.py and a spectrum analyzer to measure the IMD products directly and adjust the transmit power until they meet your specification. Johnathan _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio