Modulacion adaptativa usando BPSK, QPSK y 16QAM

Debo diseñar e implementar un sistema de comunicaciones inalámbricas basado en la plataforma USRP B210 y Simulink, capaz de transmitir datos (texto, audio o imágenes) entre estos dos dispositivos, adaptando automáticamente el esquema de modulación ya sea BPSK, QPSK y 16QAM en función de la calidad del canal, con el fin de optimizar la fiabilidad y la velocidad de la transmisión.Por donde deberia empezar? Como podria obtener la calidad del canal en la trasmision para asi determinar la modulación y poder trasmitir? Deberia usar simplex, duplex o semiduplex?

Answer 1

[Meet]

Hi @Diego Alejandro,

• You could start by running existing Simulink examples such as "QPSK Receiver with USRP Hardware in Simulink". These illustrate key components like AGC, synchronization, frequency correction, and frame handling (https://www.mathworks.com/help/comm/usrpradio/ug/qpsk-receiver-with-usrp-hardware-in-simulink.html). After running this example you could reliably, extend it to include BPSK and 16QAM.
• To choose the modulation dynamically, implement a quality metric such as "EVM", using Simulink’s EVM Measurement block "SNR", computed from signal vs. noise power with built-in or custom blocks or "BER", measured in real time by comparing received data to known preambles.
• Full-duplex is complex due to self-interference, simplex would not allow feedback. The practical solution is half-duplex alternate between transmit and receive slots so the receiver can send channel quality feedback back to the transmitter.

Hope this helps!