Learn SDR 22: GPS Gold Codes; Spread Spectrum; Code-division multiple access (CDMA)
Channel: HarveyMuddPhysicsElectronicsLab
Date: 2022-10-13

CORRECTION: In the last third of the video, I say that there is a new bit of data at 100 Hz, with each bit being 10 cycles of the 1023-bit Gold code.  My memory was wrong. Bits are transmitted every 50 Hz, with each data bit XORed with 20 complete cycles of 1023 chips. Thank you to okan erturk for correcting me in the comments.

Gold Codes are XORed combinations of taps from Linear Feedback Shift Registers (LFSRs). This is used in spread-spectrum communications, including the Code-division multiple access (CDMA) that GPS satellites use.

https://gallicchio.github.io/learnSDR/lesson22.html

All GNURadio flowgraphs are at:
https://github.com/gallicchio/learnSDR

--- Learn SDR with Professor Jason Gallicchio