A concurrent dual-band receiver based on a single multiport correlator is proposed in this brief to down-convert dual-band radio frequency signals. The system configuration, output power, as well as its spectrum analysis are discussed, and then a generalized baseband signal recovery theory is put forward. Next, the calibration algorithm based on real-valued time-delay neural network, which can take the system impairments and signal distortions into consideration, is proposed to retrieve two baseband signals, simultaneously. Finally, the six-port receiver is tested under the common modulated signals, and the measured error vector magnitudes between the transmitted and the received signals are all less than 2%.