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This tutorial allows students to build a software-defined receiver to demodulate an OFDM packet. The signals we use in the tutorial were transmitted and received over the air on the POWDER wireless testbed. Students have the receiver do synchronization, dropping of the cyclic prefix, performing the FFT, doing channel estimation using the pilot data, and then coding a symbol decision block. The bits generated from this are used to generate a string, which lets the student know that they have successfully completed the receiver design.
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QPSK Receiver Tutorial: Over-the-air SDR Implementation for Narrowband QPSK Receiver
This tutorial allows students to build a software-defined receiver for a narrowband QPSK receiver. The receiver starts with a QPSK signal recorded over-the-air on the POWDER wireless network. Then it walks the student through synchronization in time, frequency, and phase. The student builds in convolution and downsampling. Then the student codes the symbol detector and appends bits to the output. At the end, they convert the bit vector to a string message that shows them that they successfully built the receiver.
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- PAR ID:
- 10667097
- Publisher / Repository:
- https://github.com/npatwari/QPSK-RX-Tutorial
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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