2.4 GHz Zero-IF Receiver for Active Integrated Antenna

Abstract

This paper discusses the design and simulation of a compact miniature integrated antenna using direct conversion detection at 2.4 GHz. In this receiver design, Agilent’s ADS software using momentum simulation and circuit simulation is employed to analyze the entire structure. Proximity- Coupled Feed Antenna is integrated with 900 hybrid coupler, oscillator and diodes mixer for zero-IF or direct conversion detection is presented here. ProximityCoupled Feed Antenna that is presented here has a bandwidth up to 7.7188 % bandwidth. The 90 hybrid coupler can act as a phase shifter to provide the necessary 900 characteristics to operate with I and Q signal for direct conversions. Two schottky diodes are mounted onto each of two coupler’s output port to act as a mixer. One pin of the diodes is connected to the edge of output port and the other pin is grounded via a small hole to ground plane. In the simulation mode, 10 MHz signal have been generated and modulated through out the circuit. This receiver is then demodulated the signal and detected at the two output port. The signal output and demodulated spectrum is shown in this paper. In the measurement mode, 1 kHz sinusoidal signal act as a baseband have been generated and modulated using signal generator. The demodulated signal is detected using zero IF receiver circuit and the baseband signal at the output ports is successfully detected using oscilloscope.