Utility-optimization dynamic subcarrier allocation algorithm for SC-FDMA systems

Two utility-optimization dynamic subcarrier allocation(DSA) algorithms are designed for single carrier frequency division multiple access system(SC-FDMA).The two proposed algorithms aim to support diverse transmission capacity requirements in wireless networks,which consider both the channel state information(CSI) and the capacity requirements of each user by setting appropriate utility functions.Simulation results show that with considerable lower computational complexity,the first utility-optimization algorithm can meet the system capacity requirements of each user effectively.However,the rate-sum capacity performance is poor.Furthermore,the second proposed utility-optimization algorithm can contribute a better trade-off between system rate-sum capacity requirement and the capacity requirements of each user by introducing the signal to noise ratio(SNR) information to the utility function based on the first utility-optimization algorithm,which can improve the user requirements processing capability as well as achieve a better sum-rate capacity.

Application of PI Control Algorithm to Discrete Manufacturing Systems

PI （proportional-integral） control algorithm is applied to control WlP （work-in-progress） in a discrete manufacturing system, where the cascade control of PI controllers is presented. It is in the frequency domain that the PI controller is designed with constraints on sensitivity options to ensure the stability and robustness of its parameters. A case is evaluated on a motorcycle engine crankcase production system, whose simulation results confirm that demand fluctuations can be compensated by PI controllers under a normal demand. PI controllers also possess low sensitivity to the distribution of production times.

The Effects of Filtered Channel Quality Feedback on Throughput of Proportional Fair Algorithm

The throughput (total bit per second per hertz) of a modified Proportional Fair Algorithm (PFA) is analyzed and computed. The modified PFA introduces a dynamic threshold to filter the feedbacks of Channel Quality (CQ) based on which the users' priorities are calculated for scheduling. Only those in good CQs (relative to their own average CQ) can be the candidates for scheduling. The results show that the modified PFA with a low CQ threshold can not only reduce some feedback overhead but also maintain the throughput of traditional PFA. Interestingly, for a certain combination of system parameters, the throughput gain over traditional PFA can be achieved by this modified PFA. Two methods of calculating priority, one based on signal to noise ratio, and the other on information rate, are considered. Their performances are generally similar in terms of throughput.

Studyon hardware-in-the-loopsimulation of beer fermentation system

Beer fermentation process is a complex biochemical reaction process.It is the most important to control temperature of the wort in fermentation tank in accordance with the beer fermentation temperature curve so as to ensure the completion of fermentation.The controlled object is characterized by large inertia,long time delay and mutual coupling of three temperature areas.Based on this,a temperature control method for beer fermentation system is designed.Using digital incremental proportion integration differentiation （PID） control algorithm,the controlled quantity is transmitted to the controlled object after diagonal matrix decoupling.This simulation system can be completed in laboratory using VB and Kingview software,so it has the features of good security and low cost.It is very suitable for experimental teaching.

Improved proportional fair dynamic subcarrier allocation with frugality constraint for SC-FDMA system

With the objective of taking full use of channel resource, we proposed two utility based dynamic subcarrier allocation （DSA） algorithms for the single carrier frequency division multiple access （SC-FDMA） system, which are the proportional fair frugality constrained （PF-FC） algorithm and the weighted proportional fair frugality constrained （WPF-FC） algorithm. The two proposed algorithms are designed under the frugality constraint （FC） control consideration so as to avoid service rate waste and improve the spectrum efficiency. Moreover, the queuing buffer model in this paper is established on a finite size structure rather than the traditional infinite queuing manner, which is more consistent with the practical transmission condition. Simulation results indicate that the two proposed algorithms can both achieve significantly better system rate-sum capacity and quality of service （QoS） performance than their primary algorithms, and are more applicable for the heterogeneous traffic.