Receiver for Dual Band Applications

This dual-band CMOS receiver for GSM and DCS1800 applications incorporates hardware sharing between two paths to reduce the number of off-chip components [1]. The receiver is an extension of the Weaver single-sideband architecture [2]. Utilized in References 3 and 4, the Weaver architecture performs two consecutive quadrature downconversion operations on the signal and the image such that if the final outputs are added, the signal is obtained and the image is suppressed and if they are subtracted, the reverse occurs [5]. The fact that the addition or subtraction of the outputs in the Weaver architecture can select or reject two bands symmetrically located around a local oscillator (LO) frequency provides the foundation for the work reported here.