t ware project, if there is a design error, it is as simple as -125 dBm, the intermodulation products from two backspace, type, and enter to fix the problem. narrowband terms must be below this level. If the Fortunately, the last decade has seen significant products must be below -130 dBm, and they are gen- advances in semiconductor technology that have erated by a -45 dBm tone, then an input referred IP3 of caused impressive gains [17] not only in performance but -2.5 dBm is required, or in terms of single-tone per- also in cost. SDR is one area that has greatly benefited formance with a -30 dBm in band blocker, a -100 dBFS from these varied technologies and will continue to do SO performance. Clearly, from the single-tone re- as the meaning of SDR is developed, just as has been the quirements, narrowband performance will be limited by case in the history of programming languages. the harmonics of the blockers more SO than sensitivity. Although SDR is not the solution to all communi- Clearly, this design maintains good performance for cation problems, it will offer robust solutions to chal- both CDMA2000 and UMTS while retaining the ability lenging design issues in the coming years. These issues to perform reasonably well at narrowband standards. include phased array technology, location services, in- Although this review is not exhaustive, it does indicate teroperability, and complex concepts yet to be defined. a methodology for looking at multimode radio perfor- However, there are still some challenges preventing full mance. Since this is a wideband receiver, the simulta- acceptance of this technology. The two main issues are neous reception in all three modes is possible providing cost and power. Interestingly, these two have a that the digital processing is available (i.e., multi-carrier). first-order positive relationship; solve one problem and Likewise, this receiver is suitable for field configuration the other will only get better. Without low power, user between these modes, even if it is not operated i