Design of RF Receiver Front-End with Bandpass and Hairpin Resonator Narrow Band Filter for High Speed Intelligent DSRC Application

In this paper, RF receiver front-end applying high speed intelligent DSRC (Dedicated Short Range Communication) systems is presented. The proposed chip includes a current-reused LNA, a folded Giber cell mixer, a Colpitts VCO, and SIR pseudo-inter digital bandpass filter. This design of the 5.8GHz band filter design using micro strip structures like pseudo-inter digital cavity to form band-pass filters, impedance matching to enhance this through a different filter device's performance. Band pass filter center frequency at 5.8 GHz, insertion loss of 2.5dB, band-pass of the return loss is about 20 dB. A cross-coupled planar microwave elliptic function filter using coupled microstrip miniaturized hairpin resonators at the frequency 5.8 GHz band is designed and implemented. To construct band pass filter, parallel and series resonance characteristics of electrical, magnetic or mixed coupling are discussed. Theoretical analysis is used to illustrate the different coupling functions. The designed hairpin resonator narrow band pass filter achieves a measured bandwidth of 30 MHz, an insertion loss less than 1.4 dB and return loss higher than 30 dB. The measured results show an input return loss of 20 dB, a conversion gain of 29 dB, a double-side band (DSB) noise figure (NF) of 5 dB, and a third-order intercept point (IIP3) of -24.4 dBm. The on-chip oscillator shows the measured tuning range of 5.17-5.98 GHz and phase noise of 118.5 dBc/Hz at 1 MHz offset from the 5.8 GHz carrier with a power consumption of 27.6 mW from a 1 V supply voltage.