 the required operational bandwidths, duplex spacing and duplex gap of each option expressed as a percentage of the centre frequency combined with the amount of unwanted spectral energy likely to be introduced from proximate spectrum, a particular issue for the 700- and 800-MHz band plans or L band at 1.5 GHz (adjacent to the GPS receive band). The performance of a phone from one end of a band to the other can also vary by several dBs. Adaptive-matching techniques can help reduce but not necessarily eliminate this difference. At present, a user device parked on a mismatched channel on the receive path will be, or at least should be, rescued by the handover process but the associated cost will be a loss of network capacity and absorption of network power (a cost to others). So there are two issues there, a performance loss that translates into an increase in per bit delivery cost for the operator, and commercial risk introduced by either late availability or nonavailability of market competitive performance products capable of accessing these new bands. The market risk is a function of the divide down effect that multiple standards and multiple bands have on RF design resource. The industry's historic rate of progress with new band implementation has been slow. GSM phones were single band in 1991, dualband by 1993, triband a few years later, quadruple band a few years later and quintuple band a few years Wireless User Hardware M7400 Transceiver Architecture with additional band support ERICSSON LTE, HSPAevo, Rx MIMO signal processing Diversity/MIMO front-end LTE, HSPAevo, Rx signal processing Main PA 'Core' WCDMA combination with international roaming LTE, HSPAevo, Band 1, 2, 4, 5 (6), 8 - - Quadband GSM Tx signal processing Add on Additional high band support: e.g. band 3, 7, 11 or 40 Additional low band support: Add on e.g. band 12-14, 20 ERICSSON Figure 5.8 Block diagram of multiband multimode RF front end. Reproduced with permission of ST Ericsson. 21 later. A five-band phone remains a common denominator produ