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A test for underwater code division multiple access in a water tank

Code division multiple access (CDMA) is a promising medium access control (MAC) protocol for underwater acoustic sensor networks because of its robustness against frequency selective fading, high frequency reuse efficiency, and fewer control packets for data transmission. In this study, we design a two-channel CDMA transceiver to operate in underwater acoustic channel environments, and we evaluate the feasibility of underwater CDMA using a water tank experiment. Two users' data are spread and orthogonally multiplexed using a Walsh code. Subsequently, a pseudorandom noise (PN) code acquisition process is added for phase error correction in the receiver.