Barker Code Generator
Barker Code Generator
(OP)
Hello,
I am looking for a _simple_ circuit to generate a Barker code sequence (11101101, if I remember correctly). I was thinking of using a PIC10F200 to do this, but I feel that the PIC is a little "overkill" for this application.
Do you know any logic circuit or any alternative method to generate such sequence? Thank you in advance!
Best regards,
James
I am looking for a _simple_ circuit to generate a Barker code sequence (11101101, if I remember correctly). I was thinking of using a PIC10F200 to do this, but I feel that the PIC is a little "overkill" for this application.
Do you know any logic circuit or any alternative method to generate such sequence? Thank you in advance!
Best regards,
James





RE: Barker Code Generator
TTFN
RE: Barker Code Generator
It is used all the time for stuff; like my Direct Synthesis Signal Generator.
RE: Barker Code Generator
Best regards,
James
RE: Barker Code Generator
ht
RE: Barker Code Generator
(I've never understood why Barker Codes aren't used 'everywhere'.)
RE: Barker Code Generator
Barker Code info:
http://mathworld.wolfram.com/BarkerCode.html
RE: Barker Code Generator
If you don't have that noisy a channel, then any simple error correcting code will be more efficient from total data bandwidth.
A simple 8 bit ECC on 64 bits is only 12.5% more data bandwidth required, while a 13-bit Barker code is 1300% more data bandwidth required.
TTFN
RE: Barker Code Generator
The definition of Barker Codes includes this 'sidelobe' characteristic. There's only a handful of codes that have this characteristic and the longest is 13-bits in length.
The first time that I met them was in a radar system where they're used to peak-up (by 13:1) the return thus improving SNR.
If your signal is relatively low bandwidth, then making it slightly wider with a Barker Code is free.
Apologies for disagreeing again...
RE: Barker Code Generator
TTFN
RE: Barker Code Generator
RE: Barker Code Generator
IRstuff first mentioned the pre-loaded shift register. That is simpler than a PIC, but might not cost much less.
RE: Barker Code Generator
Anyway, I am having some troubles connecting the PIC10F200 to ICD 2 now. I got these messages:
Programming Target...
ICDWarn0044: Target has an invalid calibration memory value (0x400). Continue?
...Validating configuration fields
...Erasing Part
...Programming Program Memory (0x0 - 0x22)
...Loading DebugExecutive
Verifying...
...Program Memory
ICD0161: Verify failed (MemType = Program, Address = 0x0, Expected Val = 0xA01, Val Read = 0x0)
ICD0275: Programming failed.
MPLAB ICD 2 Ready
I read somewhere that I need to apply 12V at Vpp. I did that but it made no difference. The CP bit is always turned off:
__CONFIG _MCLRE_ON & _CP_OFF & _WDT_OFF
Any other idea?
James
RE: Barker Code Generator
Make sure you have the correct chip selected (also check that your programmer supports that chip).
Dan
Owner
http://www.Hi-TecDesigns.com
RE: Barker Code Generator
RE: Barker Code Generator
RE: Barker Code Generator
best regards,
RE: Barker Code Generator
Also, there are generaized Barker codes. Use complex +/- j and +/-1 as your chips.