How to obtain good performance by iterative and diversity techniques for uplink MC-CDMA systems

2006 ◽  
Author(s):  
Y. Yuan-Wu ◽  
M. Sarkiss ◽  
Ye Li
Keyword(s):  
Diversity Techniques ◽  
Cdma Systems

scholarly journals Space-time diversity signal processing employed by W-CDMA systems

2019 ◽  
Vol 64 (3) ◽  
pp. 332-346
Author(s):  
V. P. Tuzlukov
Keyword(s):  
Mobile Station ◽  
Base Station ◽  
Space Time ◽  
Prediction Algorithm ◽  
Frequency Diversity ◽  
Transmitter Diversity ◽  
Diversity Techniques ◽  
Maximum Ratio Combining ◽  
Cdma Systems ◽  
Code Division Multiple

Transmit diversity under transmission of signals from the base station to mobile station using the code-division multiple-access (CDMA) system allows us obtaining the performance gains close to the mobile station receiver diversity without complexity of the mobile station receiver antenna array. The multipath diversity can be achieved using the pre-RAKE precoding at the transmitter that could be employed and there is no need to install the RAKE receiver at the mobile station. We investigate several transmitter diversity techniques employed by wideband CDMA (W-CDMA) systems. We also study a possibility to combine transmitter diversity and precoding that achieves the gain of maximum ratio combining of all space and frequency diversity branches jointly with long-term prediction algorithm. It was demonstrated that the performance of the space-time pre-RAKE method approaches the performance of the maximum ratio combining for all space and frequency diversity branches. It is shown that all closed loop methods depend on the long range prediction to approximate the ideal performance in the fast fading environment.

Evaluation of Cooperative Diversity Techniques Using STC for Future S-DMB Services

2009 ◽  
Vol E92-B (11) ◽  
pp. 3345-3353 ◽  
Author(s):  
Sooyoung KIM ◽  
Unhee PARK ◽  
Hee-Wook KIM ◽  
Do-Seob AHN
Keyword(s):  
Cooperative Diversity ◽  
Diversity Techniques

Study of Power Control in CDMA System on the basis of optimization Technique

2017 ◽  
Vol 7 (8) ◽  
pp. 126
Author(s):  
. Geetanjli
Keyword(s):  
Power Control ◽  
Multiple Access ◽  
Optimization Technique ◽  
System Optimization ◽  
Base Station ◽  
Particle Swarm Algorithm ◽  
Cdma System ◽  
Frequency Division ◽  
Cdma Systems ◽  
Time Division

The power control in CDMA systems, grant numerous users to share resources of the system uniformly between each other, leading to expand capacity. With convenient power control, capacity of CDMA system is immense in contrast of frequency division multiple access (FDMA) and time division multiple access (TDMA). If power control is not achieved numerous problems such as the near-far effect will start to monopolize and consequently will reduce the capacity of the CDMA system. However, when the power control in CDMA systems is implemented, it allows numerous users to share resources of the system uniformly between themselves, leading to increased capacity For power control in CDMA system optimization algorithms i.e. genetic algorithm & particle swarm algorithm can be used which regulate a convenient power vector. These power vector or power levels are dogged at the base station and announce to mobile units to alter their transmitting power in accordance to these levels. The performances of the algorithms are inspected through both analysis and computer simulations, and compared with well-known algorithms from the literature.

Sign in / Sign up

Export Citation Format

Share Document