[Discuss-gnuradio] packet sending interval

[Guanbo Zheng]

Hi, 

I am using the OFDM benchmark code in USRP2, where my system is Ubuntu 9.10 + Gnuradio 3.2.2.
Basically I used the following scripting for TX and RX:
$  sudo python benchmark_ofdm_tx_new.py
--mac-addr=00:50:c2:85:32:97 -f 2.462G -m qpsk -i 100 --tx-gain=30 -M 8
-s 1000 --fft-length=512 --occupied-tones=200 --cp-length=128
$ 
sudo python benchmark_ofdm_rx_new.py --mac-addr=00:50:c2:85:32:99 -f
2.462G -m qpsk -d 100 --rx-gain=30 --fft-length=512
--occupied-tones=200 --cp-length=128

As observed from spectrum analyzer, I found out the OFDM symbols are NOT stably transmitting. Furthermore, the packet sending interval is large ( in low rate)
Then, how can I control the sending rate/interval of OFDM packets?

The related code for "send_pkt" is as follows:
-------------------------------------------------------------
 def send_pkt(self, payload='', eof=False):
        """
        Send the payload.

        @param payload: data to send
        @type payload: string
        """
        if eof:
            msg = gr.message(1)              # tell self._pkt_input we're not sending any more packets
        else: 
            info = ofdm_packet_utils.get_info(payload, self._regime, self._symbol_time)
        N_cbps            = info["N_cbps"]
        N_bpsc            = info["N_bpsc"]
            N_rate            = info["rate"]
        N_sym             = info["N_sym"]

        (pkt,Length) = ofdm_packet_utils.ftw_make(payload,self._regime, self._symbol_time)
        (pkt_scrambled,Length) = ofdm_packet_utils.scrambler(pkt,Length)            
        pkt_coded = ofdm_packet_utils.conv_encoder(pkt_scrambled, Length, self._regime, N_cbps, N_bpsc, N_sym, N_rate)    
        pkt_interleaved = ofdm_packet_utils.interleaver(pkt_coded , self._regime, N_cbps, N_bpsc)
        msg = gr.message_from_string(pkt_interleaved) 

        self._pkt_input.msgq().insert_tail(msg)
-----------------------------------------------------------------------------------
Thanks


-- 
Regards,
Guanbo