A direct conversion receiver analysis for multistandard wireless applications

This paper presents a direct conversion receiver modified for tri-band operation (GSM900/GSM1800/PCS1900). The IF stage in zero frequency, splits into I and Q branches while offset cancellation takes place in the digital domain and is not included in the objectives of this paper. The overall receiver performance is evaluated in terms of the noise figure, intermodulation, blocking requirements, SNR, and C/I. Multimode operation is ensured by the fulfillment of the most demanding system specifications among the three participants. The complete system analysis that was carried out using HP-ADS, subjects the receiver into four different sets of tests and the main objective is the extraction of feasible building block specifications in order to guide a silicon design process.