Hi,
I'm trying to receive a live signal from an antenna on the roof through a cable connected to my SDR (hackrf one ).The bandwidth of the DVB-T in ireland is 8 Mhz , and the parametetrs Here in ireland as following:
Bandwidth: 8 MHz
Stream code rate (hi prio): FEC 2/3
Stream code rate (lo prio): FEC 2/3
Modulation: QAM 64
Transmission mode: 8k mode
Guard interval: 1/32
Hierarchy: none
net_data_rate = 24.128 Mbits/s
I used dvbt_rx_demo_8k_QAM64_rate78.grc flow graph with the following changes :
-
frequency of hackrf one = 570 Mhz, sampling rate = ((8*8e6)/7).
-
Cyclic Prefix to (8192/32, is this right?)
-
Code Rate HP : 2/3
-
Code Rate LP : 2/3
-
Guard Interval : 1/32
The problem i have is that no output data coming out after the demod_reference_signals BLOCK(no cancellation map), and got the following:
restart aquisition
OOrestart aquisition
d_freq_offset: -5
Od_freq_offset: -5
d_freq_offset: -5
d_freq_offset: -5
d_freq_offset: -5
d_freq_offset: -5
d_freq_offset: -5
d_freq_offset: -5
restart aquisition
OOd_freq_offset: -5
d_freq_offset: -5
so I had to add a signal source to shift the signal. After shfting the signal i got the following :
restart aquisition
restart aquisition
restart aquisition
restart aquisition
Orestart aquisition
I have read a lot about DVB , mapping ,ofdm and others, i have spent weeks on this but still the same problem, if it is synchronization problem what i should do?
So please i need a some help with this problem .
Thanks
Ihab
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