r drain. Note that apparent efficiency gain in RF power amplifiers can be achieved by trading efficiency against modulation accuracy (error vector magnitude). This is not a real gain as the link budget will be the same or possibly worse. From both an individual and group perspective it is better to talk quietly and clearly rather than shout loudly and indistinctly. Making Telecoms Work 5.7 Other Costs Improved performance in one functional area often introduces cost and complexity in another. These costs can include standardisation costs and the costs of testing component or product compliance with those standards, for example: 5.7.1 RF Baseband Interface Complexity Mobile RF devices have an RFIC front end with a digital bus on the back end that connects to a baseband IC. There has been substantial discussion as to how, whether or when, to standardise these control and communication interfaces between the RF and transceiver and baseband functions in the handset. One present initiative is the Dig RF work group that is supported within the MIPI alliance. 35 Version 4 of this standard increases bus speed from 300 Mbps to 1.5 Gbps SO that it can be compliant in terms of throughput, timing and latency control with LTE protocols. The functioning of these protocols requires robust testing. Testing involves the use of active probes with ultralow-capacitive loading (less than 0.15 pF) and high sensitivity (needed to work at 1.5 Gbps and 200 mVp_p). Although the required test investment is of the order of $50 000 dollars or more, the net benefits for handset manufacturers in terms of subsystem interchangeability seem to be substantial. Handset vendor support of Dig RF is consistent with initiatives in other areas (for exam- ple, the standardisation of baseband RF and smart antenna interfaces in base stations) as a mechanism for achieving a broader base of multisource interchangeable components. Many of the new adaptive techniques (adaptive matching and adaptive linearisation) require broader visibility to the physical laye