The direct conversion method used for receiver circuit. This method converts the received signal into frequencies that can be demodulated once, which reduces the number of PLL circuits and Mixer compared to the double conversion method.
It is the most suitable method for miniaturization and small area.
AK2401A which is adopted direct conversion method is suitable for miniaturization of the receiver by high integration of the receiver circuits.
The built-in receiver circuits of AK2401A are LNAs, quadrature demodulators, PGAs, 24-bit delta-sigma modulated ADCs, and bandwidth-variable digital filters, and it is 7-mm-square LSI.
High sensitivity can be achieved by receiving Gain and low NF, and high disturbance immunity can be achieved by isolation of input and output and built-in filter. In addition, the external filter after the LNA can improve the disturbance characteristics.
Receiver Circuit Downsizing using direct conversion method
Small-area transmitter and receiver circuit can be configured by using external VCOs (Voltage Controlled Oscillator) and Power Amp, as shown in Fig.1.
AK2401A evaluation boards and FPGA control boards are available for easy evaluation.
Contact us if you wish to have a sample or evaluation board.
Evaluation example on evaluation board
FPGA with simple demodulator and BER-counter
Various modulation methods such as FM, FSK and π/4DQPSK can be used to characterize the system.