In this GNU Radio demo repeated copies of a text file are modulated with BPSK scheme, transmitted by HackRF One over the air and received with RTL-SDR device. A preample of 2 bytes length was used to mark the position of the first byte in the text file, so that to achieve bit alignment and the proper reception of characters.
GNU Radio Parameters:
Carrier Frequency: 735 Mhz
Modulation scheme: BPSK
Data encoding : differential
Symbol Rate: 0.125 Msamples/sec
Sample rate at the transmitter: 0.5 Msamples/sec:
Sample rate at the receiver: 1 Msamples/sec:
Bit rate: 0.25 Mbps
Pulse shaping filter: Root raised cosine (alpha=0.40)
Timing and phase synchronization are done with Polyphase Clock Sync and Costas Loop blocks respectively.
Software:
Host 1 (transmitter): Low end PC (Core2Duo CPU
[email protected], 3Gb RAM)
OS: windows 7, Gnu Radio 3.7.13.5
Host 2 (receiver) :
OS: Ubuntu 18.04 LTS, GNU Radio 3.8.5