thranduil
Member level 1
Hi all guys,
I am currently working on a very simple communication simulator between sensor nodes operating in 434 MHz ISM band. The communication is rather simple. Nodes use FSK modulation and Manchester encoding. Correctness of the data is proved via CRC. Messages are in total 12 bytes long. At the moment I am at the point where I need to calculate Packet Error Rate for the received packet. One way to do this would be to calculate BER based on known formula for cohherent FSK reception. On the other hand, when I think about this communication, I believe that some kind of error correction would be possible with Manchester encoding and CRC. So, if I detect symbol error in Manchester sequence, I could assume different value and continue with reception. At the end of the frame, CRC should show if my correction was correct or not.
Let say that transmitted Manchester sequence is given as: ... 01 01 10 01 ... . If received sequence is ... 01 01 10 00 ... I will detect invalid Manchesre sequence. From this point I could assume that correct sequence was:
... 01 01 10 01 ... or
... 01 01 10 10 ...
from this point I would continue with collecting symbols. At the end I would check CRC for both cases.
By now, I was not able to find any source on the Web and read theoretical background, ... I wanted to ask you if you can give some directions how to search for this, cause I tried combinations with following terms: error correction, manchester encoding.
Thanx in advance
I am currently working on a very simple communication simulator between sensor nodes operating in 434 MHz ISM band. The communication is rather simple. Nodes use FSK modulation and Manchester encoding. Correctness of the data is proved via CRC. Messages are in total 12 bytes long. At the moment I am at the point where I need to calculate Packet Error Rate for the received packet. One way to do this would be to calculate BER based on known formula for cohherent FSK reception. On the other hand, when I think about this communication, I believe that some kind of error correction would be possible with Manchester encoding and CRC. So, if I detect symbol error in Manchester sequence, I could assume different value and continue with reception. At the end of the frame, CRC should show if my correction was correct or not.
Let say that transmitted Manchester sequence is given as: ... 01 01 10 01 ... . If received sequence is ... 01 01 10 00 ... I will detect invalid Manchesre sequence. From this point I could assume that correct sequence was:
... 01 01 10 01 ... or
... 01 01 10 10 ...
from this point I would continue with collecting symbols. At the end I would check CRC for both cases.
By now, I was not able to find any source on the Web and read theoretical background, ... I wanted to ask you if you can give some directions how to search for this, cause I tried combinations with following terms: error correction, manchester encoding.
Thanx in advance
