Radio as we know has continued to evolve for nearly a century. Going from heterodyne to superheterodyne to direct conversion on the architectural side, it has constantly tapped the benefits of advances in semiconductor technologies. With the emergence of semiconductor transistors in the early 1950s, we know bulky radio receivers based on tubes were transformed into compact portable devices, making its way into markets that were unthinkable with tubes. And automotive is one of them.

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Now, with the digital revolution under way since the early 1990s, it is again going through transformation. While the radio broadcasters have exploited the availability of high-performance data converters and digital processors to bring high CD-quality performance to analog AM and FM bands, digital signal processing (DSP) chips have been at the center of revolution in wireless and cellular communications.

On the radio broadcast front, development efforts of more than five years have resulted in digital radio services. Using S-band frequency spectrum, two satellite radio service providers — XM Satellite Radio and Sirius Satellite Radio — have been pounding the airwaves to send digital signals toward automobiles. Now, the traditional terrestrial service broadcasters are ready to join the fray. Thanks to DSP and high-performance data converter chips, terrestrial AM and FM is ready to go the digital way with the emergence of the HD Radio standard developed by iBiquity Digital Corp. Formerly known as in-band, on-channel (IBOC), the HD Radio uses the same frequency and spectrum as the current analog systems.

Despite all the advances, the fundamental radio architecture has remained hardware intensive. With the wireless revolution under way, mobile/cellular standards are changing rapidly, and newer ones coming sooner than operators can handle, there is a need for a new radio architecture that can handle this sea of change instantly. Every consumer has experienced this problem in one way or the other. Signals disappear instantly as you go from place to place or there is noise and interference in certain locations. Plus, you have to change phones as you go from one coast to another, or from one country to another. And, you always wondered if there was ever going to be a single radio unit that could handle all these changes, and you could travel without having to worry about changing hand phones or carrying multiples in a brief case when traveling.

Well, help is on the way. Software-defined radio or SDR promises to deliver that needed radio architecture that can alleviate the problem. And, the recent leap in DSP processing capability as cost and power consumption climbs down, as well as a surge in density of lower-priced FPGAs are paving the way for commercial deployment of software-intensive radio. By supporting all existing and emerging wireless standards concurrently via software upgrade, it promises a new era in wireless communications, where-in reconfiguration and upgrades of wireless equipment and cellular handsets is only a matter of software upload or download. Although, it is touted as the future of wireless communications, that future is already here.

In fact, military researchers and developers have been the early drivers of SDR innovation, with its Joint Tactical Radio System (JTRS) providing the main impetus for SDR technology since the mid-1990s. Toward that end, the JTRS developers have created what is called software communications architecture (SCA) that provides the framework needed to process multiple waveforms and reconfigure architectures.

For the commercial deployment of software radio, SDR Forum, a nonprofit industry organization, is playing an active role in garnering international support and generating standards for expediting its deployment in the consumer world. Concurrently, the SDR Forum has commissioned a veteran analyst to conduct a comprehensive SDR market study. Wireless OEMs and service providers who see the benefits of deploying base stations and handsets that can quickly switch between myriad configurations and process multiple, multimode waveforms and protocols in a single unit, are rapidly moving in that direction. In reality, some have already taken that step.

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