This study proposes mainly 2 different backscatter medium access control (MAC) protocols. Both proposed protocols work for half-duplex and full-duplex transmission modes in a bistatic backscatter system. The first one, namely express backscatter MAC (XBM), allows higher transmission rates in a bistatic backscatter network, aiming to increase network capacity. It takes advantage of carrier signals for faster transmissions whenever they are generated. The second protocol, reliable backscatter MAC (RBM), provides more reliability to the backscatter transmission, especially when hidden nodes exist. It brings more reliability by introducing a two-step CTS_to_Self mechanism to separate backscatter communication from Wi-Fi communication and avoid hidden node problem. In addition, our MAC protocols enable simultaneous backscatter transmissions at the MAC level by letting several tags carry their data on the same carrier signal. We evaluated and compared our proposals through numerical analyses that highlighted agreeable performance levels.
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