Segment Design Tradeoffs I. OVERVIEW The six steps in the systems-level design process associated with the software radio are illustrated in Figure 6-1. The tradeoffs proceed from front end to back end. The choice of antennas (step 1 in the figure) determines the number and bandwidth of RF channels (step 2). This, in turn, constrains the numbers and bandwidths of ADCs (step 3). Some waveforms may require dedicated ASICs (e.g., W-CDMA despreaders) in front of the ADCs. Additional parallel IF processing and ADC paths may be necessary to support multiple-service bands simultaneously....

Smart Antennas Smart antennas are an important application of SDR technology [381]. An in-depth treatment is beyond the scope of this chapter. The objective is to introduce the topic to identify the implications of smart antennas for softwareradio architecture. The smart antenna is a logical extension of antenna diversity described above [382]. Smart antenna arrays integrate the contributions of spatially distributed antenna elements to provide wireless communication systems with larger capacity and higher link quality through frequency reuse and cochannel interference suppression [383, 384]....

This chapter develops illustrative applications, including the design of a contemporary SDR infrastructure product, the disaster-relief system. I. THE DESIGN PROCESS The implementation of SDR applications can be structured into an SDR design process. This process begins with the definition of a concept of operations (CONOPS), in which functions of the product are identified. The next stage, system definition, includes rapid prototyping and benchmarking. The third stage, system development, includes the implementation of hardware-software components. ...

Reference Architecture This chapter provides a consolidated view of the software-radio architecture models developed throughout the text for convenient reference. This consists of a radio platform view (Figure 16-1) and a software components view