6. Transceiver I: Transmitter Architectures

In the previous chapters, we described the three major subsystems of modulation, demodulation, and power amplification in wireless communication systems. Starting with Chap. 6, we move to a top level, or the transceiver architecture that includes other functional blocks besides these three subsystems to achieve complete transmission and reception. In general, there are three types of common transmit and receive architectures available to the wireless radio frequency (RF) IC transceiver architect: superheterodyne, low (IF), and direct conversion, also known as zero-IF. Each of these architectures has its own advantages and disadvantages, and some of the potential issues related to the particular architecture can be minimized with either careful circuit design techniques or calibration methods. We describe and analyze what advantages and disadvantages these architectures have in practical applications and what challenges RF IC designers may face in their designs, and we discuss some of these design techniques and calibration methods in more detail in the subsequent chapters.