A dual-band multiport receiver apparatus and a dual-band (or multiband) multiport transmitter apparatus are disclosed. The receiver apparatus may include: a multiport circuit having a plurality of 90-degree hybrid couplers and a power divider to generate a plurality of radio frequency (RF) signals based on a dual-band signal, a plurality of diode networks connected to the multiport circuit to generate a plurality of intermediate frequency (IF) signals based on the plurality of RF signals, two analog-to-digital converters (ADCs) connected to the diodes to convert the IF signals to two digital signals, and a digital signal processor connected to the ADCs to decode information carried by the dual-band signal based on the two digital signals.