Implementation of the signal component generator of a CALLUM 2 transmitter architecture in CMOS technology

This article presents an analog implementation of the signal component generator (SCG) of the CALLUM 2 linear transmitter architecture. The proposed SCG is suited for integration in a standard 0.35 μ m CMOS process, and has from simulations proven to be adequate when operating on an EDGE modulated baseband signal with a data rate of 270.833 ksymb/s. The total current consumption of the SCG is 2.0mA from a 3.3 V supply. A variable gain amplifier (VGA) with common-mode (CM) control is presented, and the VGA is inserted in between the SCG and the voltage-controlled oscillator (VCO) to adjust the loop gain, which has strong influence on the stability and spectral performance of the linear transmitter architecture.