A Novel High Data Rate Prerake DS UWB Multiple Access System and its Accurate Interference Model

Author(s):  
Wei Cao ◽  
A. Nallanathan ◽  
C. C. Chai
2016 ◽  
Vol 10 (17) ◽  
pp. 2427-2434 ◽  
Author(s):  
Jianqing Dou ◽  
Zaichen Zhang ◽  
Jian Dang ◽  
Liang Wu ◽  
Yuxin Wei ◽  
...  

Author(s):  
HARSHA PRAKASH ◽  
C.D. SURIYAKALA

To meet the requirements of high data rate, third generation partnership project (3GPP) has come across the development of long term evolution (LTE). High data rate can be achieved with the help of an advanced modulation method. Orthogonal Frequency Division Multiple Access (OFDMA) was considered as a modulation method especially in the downlink of the communication systems. It gives many advantages like frequency diversity, increased capacity and robustness against impulse noise. Besides these advantages, a major drawback of OFDMA is its high peak-to-average power ratio (PAPR). High PAPR affects the system by lowering the power amplifier efficiency, increased complexity as well as shorter battery life. In case of uplink communication, where better peak power characteristics benefit the mobile terminals with respect to power efficiency, OFDMA is not a possible solution. To handle such situations, 3GPP has introduced a modified form of OFDMA which is known as Single-Carrier Frequency Division Multiple Access (SC-FDMA). It provides same advantages as OFDMA along with low PAPR. To further improve the bit error rate (BER) performance of the system and power amplifier efficiency Multiple-Input Multiple-Output (MIMO) can be extended to SC-FDMA system. This paper surveys causes, effects and possible solutions of high PAPR in a communication system.


2019 ◽  
Vol 9 (19) ◽  
pp. 4004
Author(s):  
Hesham Sadat ◽  
Mohamed Abaza ◽  
Safa M. Gasser ◽  
Hesham ElBadawy

Nowadays, visible light communication (VLC) systems have become one of the candidate technologies for high data rate indoor communications. However, the main challenge to develop a high data rate VLC system is the narrow modulation bandwidth of light-emitting diodes (LEDs). Power domain non-orthogonal multiple access (PD-NOMA) is a promising scheme to enhance the spectral efficiency of downlink VLC systems. In this paper, we introduce cooperative PD-NOMA to the system to improve the signal reception for the far users. We evaluate the bit error rate (BER) and achievable rate performance of non-cooperative and cooperative PD-NOMA under perfect channel state information (CSI). Moreover, we drive analytic expressions for the BER and provide a Monte Carlo simulation results for verifying the validity of the derived analytical BER results. The results show that cooperative PD-NOMA outperforms non-cooperative PD-NOMA by 8.2 dB at BER 10−6 and by achievable rate 14.1 bit/s/Hz at 45 dB in a two-user scenario.


1991 ◽  
Vol 21 (2) ◽  
pp. 59-70 ◽  
Author(s):  
E. C. Foudriat ◽  
K. Maly ◽  
C. M. Overstreet ◽  
S. Khanna ◽  
F. Paterra

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