 quality improves the perceived video quality will improve. Similarly, user experience opinion scores will generally be higher when the delivered quality is relatively constant and will be higher than a service that is sometimes good and sometimes bad. This has an impact on scheduling implementation but it can be generally stated that any improvements in user equipment RF and baseband performance will translate directly into a better and more consistent user experience MOS. The three companies referenced have web sites with information on voice and video MOS comparisons. Some additional standards work on application performance benchmarking may be useful in the longer term. 3.7.3 The Cost of Store and Forward (SMS QOS) and Buffering Present and future mobile broadband networks have a mix of store and forward processes whose purpose is to reduce the cost of delivery both in terms of bandwidth and energy used. An example is SMS where in extreme circumstances several hours might elapse between a message being sent and received. At the physical layer best-effort data will be buffered in the e node B or user's device to smooth out traffic loading (which reduces the offered traffic noise) and/or to take advantage of CQI-based scheduling gain. There is an alternative argument that says short term (buffering) or longer term (store and forward) has an associated memory cost that needs to be factored in to the efficiency equation - fast memory in particular incurs a capital and operational (energy) cost. There is also a plausible and probably understated relationship between receive sensitivity and data throughput in which it could be shown that an extra 3 dB of sensitivity translates into a doubling of the downlink data rate in a noise-limited environment. This could also be equated to a doubling of the user data duty cycle or a halving of the user power budget for the 8 http://www.opticom.de/. http://psytechnics.net/. http://www.radvision.com/ Making Telecoms Work same amount of data. Similarly, it can be argued that a 3