Power efficient transceivers to enable energy-efficient mobile radio systems

Energy savings in mobile networks based on adaptation to traffic statistics

“…The key approach to saving energy is to make the power consumption proportional to the traffic load, either by implementing a partial shut down of amplifiers as discussed in this article, or by employing enhanced power amplifiers. An overview of the latter is provided in [15]. During power-off of the amplifiers, further power savings can be achieved by also switching off the baseband signal processing, and indirectly, in the AC/DC power conversion and in the cooling fans.…”

“…Figure 2 demonstrates that about a third of the time the load is very low and on average the load is about 50 percent of the maximum load (which in turn is typically 30 percent to 50 percent of the installed hardware capacity). When power amplifiers [15] and other hardware components are introduced that can be operated at different power levels, or parts of the hardware can be shut down temporarily according to the traffic load, obviously a high power saving potential can be addressed. Figure 2 shows the potential energy savings when adapting the power consumption to the actual traffic load.…”

“…With rising energy prices, this has led to a situation where energy expenses equal around 18 percent of network operational cost in European markets and even more in developing countries, where diesel fuel is used to power off-grid radio base stations [21]. 1) increasing the power amplifier efficiency [15], 2) minimizing the up to 50 percent feeder losses in the radio frequency (RF) cable between the power amplifier and the antenna (e.g., by using remote radio heads), and 3) avoiding air conditioning in the cabinet (e.g., by employing fresh air cooling). All of these methods limit improvements to individual components.…”

Impact of service rates and base station switching granularity on energy consumption of cellular networks

“…They are used for transforming energy consumption from daily into monthly. The first term in brackets of the objective function (8) refers to the fixed component (P j ), while the second term concerns the variable component (P k ) of the daily network power consumption.…”

“…Increasing energy efficiency of the BS can be accomplished through a holistic approach considering improvements on: component, link, and network levels [7]. On the component level, special attention is dedicated to improving power amplifier efficiency [8], minimizing feeder losses [9], and introducing novel air cooling approaches [10]. Energy saving potential on the link level can be found in link adaptation methods [11] and discontinuous transmission realized through BS sleep modes [12].…”