In this paper, to improve the energy efficiency (EE) of multi-user multiple-input multiple-output (MIMO) orthogonal frequency-division multiple access (OFDMA) system, an Energy-efficient multiple access (EMA) scheme is proposed. It improves EE by selecting either time-division multiple access (TDMA) or space-division multiple access (SDMA) based on the no. of users or power consumption. Here, w...

The capacity of mobile protocols such as FDMA (Frequency Division Multiple Access), TDMA (Time Division Multiple Access), and CDMA (Code Division Multiple Access) systems are compared assuming perfect power control and the results are compared with the previous results. Methods of calculating the traffic capacity of such systems are discussed. CDMA can provide up-to 20 times more traffic capaci...

Recently, a distributed estimation, a type of parameter estimation problem, has been widely studied from the viewpoint of wireless sensor network (WSN) applications (1) (2). In particular, distributed estimation has been well-studied for certain WSN applications, such as environmental monitoring and precision agriculture (3)-(8). In such applications, measurements are acquired by the combinatio...