As new and more complex communication standards are developed around the globe, the demand for new transceiver architectures will also grow. However, more and more often the available capital, both financial and human, limits the designs that can be tackled. Fortunately, software radio technology is available for a select and growing group of these architectures that allow a single platform to leverage into many diverse designs. As seen here, this has many distinct advantages and is not limited to interoperability, investment retention, and great flexibility.
As with any software project, quite often the potential is only limited by the
imagination of the designer. The great advantage is that as in any software project, if there is a design error, it is as simple as backspace, type, and enter to fix the problem.
Fortunately, the last decade has seen significant advances in semiconductor technology that have caused impressive gains  not only in performance but also in cost. SDR is one area that has greatly benefited from these varied technologies and will continue to do so as the meaning of SDR is developed, just as has been the case in the history of programming languages.
Although SDR is not the solution to all communication problems, it will offer robust solutions to challenging design issues in the coming years. These issues include phased array technology, location services, interoperability, and complex concepts yet to be defined. However, there are still some challenges preventing full acceptance of this technology. The two main issues are cost and power. Interestingly, these two have a first-order positive relationship; solve one problem and the other will only get better. Without low power, user devices will not be able to take full advantage of SDR technology. Clearly, the power issue comes from the need for high-performance
components. High performance means ultra-linear devices. High-linearity devices
mean low efficiency through high-standing currents.
Therefore, if the issue of how to design high-linearity devices with lower power can be solved, and it will, then costs too will also fall, opening the door for many other applications. So the key to continued SDR development and evolution is continued device improvement down the Moore's law curve and continued interest
in flexible radio architectures. Despite these challenges, the current state of performance is more than sufficient for engineers and manufacturers to seriously begin to investigate the possibilities of SDR.
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Printed with permission from Newnes, a division of Elsevier. Copyright 2008. "RF & Wireless Technologies" by Bruce A. Fette. For more information about this title and other similar books, please visit www.newnespress.com.