GSM Muti-antenna Receiver

Hi all: I try make usrp work on Muti-antenna mode , 1 to downlink , 1 to uplink. first , i only decode downlink, it can found FCCH,but can't decode sch. any suggestion? tianxing@tianxing-MS-7345:~/gsm/airprobe-gprs/gsm-receiver/src/python$ ./gsm_reive_usrp_mono.py -c 122 A side: Flex 900 Rx MIMO B B side: Flex 900 Rx MIMO B gain_a: 45.0 gain_b: 45.0 A side: The carrier frequency is set as 959400000.0 B side: The carrier frequency is set as 959400000.0 mux_val = 0x2301 input_rate: 571428.571429 sample rate: 0.527472527473 filter_cutoff: 145000.0 filter_t_width: 10000.0 input_rate: 571428.571429 sample rate: 0.527472527473 filter_cutoff: 145000.0 filter_t_width: 10000.0 Key: '0000000000000000' Configuration: '0C' Configuration TS: 0 configure_receiver 1319360150.211137 3014114160: fcch found on position: 24508 1319360150.211206 3014114160: freq_offset: -2659.853516 1319360150.254086 3014114160: fcch found on position: 77189 1319360150.254132 3014114160: freq_offset: -261.283386 sch.c:260 ERR: conv_decode 11 1319360150.307770 3014114160: fcch found on position: 135276 1319360150.307814 3014114160: freq_offset: -2574.190186 sch.c:260 ERR: conv_decode 10 1319360150.352075 3014114160: fcch found on position: 188023 1319360150.352120 3014114160: freq_offset: -375.097321 sch.c:260 ERR: conv_decode 8