 over the first five years of their initial market launch. This improvement has now levelled off to the point where we are as close to the ultimate sensitivity of the device as the existing technology will allow (about another 3 dB) providing justification for the transition to the next generation of technology (LTE). Note that these performance curves are volume specific, technology specific and frequency specific. The performance gains are achieved by a mix of engineering effort (amortised over significant product volumes) and improved RF component tolerance control. Similar gains over time and over volume are realised in terms of adjacent channel selectivity in the receiver. Similar gains over time and over volume are also realised in terms of transmitter performance, particularly in terms of error vector magnitude, specifically the phase and amplitude accuracy of the modulated signal waveform and the close-in and wideband noise characteristics of the device. An example would be the performance variation from unit to unit of SAW filters over temperature. High market volumes over time gradually erode these device-to-device variations. Closer tolerancing of active and passive components with volume therefore translates di- rectly into uplink and downlink performance gain. These uplink and downlink gains translate directly into an improved link budget that in turn translates into either higher data rates per user and/or more users per MHz of spectrum and/or improved coverage (a decrease in network density for a given user and data density). Additionally, as the performance margin improves, RF yield improves, typically from 90% to close to 100%. Note that low RF yield will also choke handset availability, which in turn can lead to significant losses in terms of market opportunity. These performance benchmarks need to be achieved across multiple bands. Initially most UMTS handsets were designed for 1900/2100 MHz, but as with GSM (the single-band to dualband to triband to quadband transition) UMTS /LTE handsets will