I want to know that we can calculate the energy efficiency (EE) in the wireless networks. Several paper define it as bits/Joule. But in some cases, EE is greater than 1.
Let's suppose:
The normalized throughput at the destination is 2.5 bits/s/h. The transmit power is 1 watt (30dBm) and the circuit power is 0.003162 Watt (5dBm). In this case the EE can be expressed as:
EE=2.5/1.003162 that is equal 2.49 which does not make sense because efficiency is always less than or equal to 1.
Thank You for your kind reply,
Energy Efficiency metric is defined as the system throughput for unit energy consumption. Both the transmission power and the circuit energy consumption should be taken into consideration for energy-efficient communication, where the former is used for reliable data transmission and the latter represents average energy consumption of device electronics.
Please see the mentioned equations in references given below
Code:
[B][U]Equation 29.[/U][/B]
Z. Wang, Z. Chen, B. Xia, L. Luo and J. Zhou, "Cognitive Relay Networks With Energy Harvesting and Information Transfer: Design, Analysis, and Optimization," in IEEE Transactions on Wireless Communications, vol. 15, no. 4, pp. 2562-2576, April 2016. doi: 10.1109/TWC.2015.2504581
Code:
[B][U]Equation 07.[/U][/B]
S. Wang, M. Ge, and W. Zhao, “Energy-efficient resource allocation for ofdm-based cognitive radio networks,” IEEE Trans. Commun., vol. 61,no. 8, pp. 3181–3191, Aug. 2013.
You don't need to review literature to see that the equation in post #1 makes no sense. Multiplying bits/Joule with transmission power is the right calculation, it gives bits/s, the achieved transmission throughput.
because efficiency is always less than or equal to 1