Design and Development of Broadband and Compact Size IQ demodulator at 850±112.5 MHz

A design and development of a compact & broadband IQ demodulator at 850±112.5 MHz is presented in this paper. Size reduction is achieved by using cascaded slow wave cells in place of conventional transmission lines to design hybrids and power splitter. Wideband operation of demodulator was achieved by designing wide band hybrid, power divider and a lossy diode matching network. This mixer exhibits good linearity with the reported measured P1dB of 5dBm, LO isolation greater than 20 dB and a typical conversion loss of 10 dB over a fractional bandwidth of 29%. IQ demodulator can easily be fabricated by using the standard printed-circuit-board technology.