The Theory And Research Status About Marx’s Communication

In recent years, as widely used in wireless communication networks and rapid growth in the demand for wireless communications business, fewer and fewer available spectrum resources, supply and demand contradictions have become increasingly prominent, seriously affecting the quality of communication in wireless communication networks, greatly hindering the development of wireless communication networks. Cognitive radio CR is an effective way to ease the shortage of spectrum resources. Wireless network it can perceive the surrounding environment changes, active learning and understanding, so as to constantly adjust the user priority, network transmission parameters such as transfer rate to reach the entire end-to-end network performance optimization. This secondary users of SU in a wireless communications network for the study, by queuing algorithm for wireless communication network to introduce ideal model, deriving a SU blocking rates, drop rate, and throughput optimization algorithm of formulas, using OPNET simulation that SU promotion, comparison of performance indicators of other optimization algorithms, advantages and disadvantages that queuing algorithm and adaptive research in areas such as work.This to queued on the algorithm as theory tools, by assumptions node of series network property, established idealized of wireless communications network model, reduced has application in the many does not necessary but and makes research process complicates of factors, and for Yu each network node, derivation out a General of blocking rate, and dropped rate and throughput of algorithm formula, and using OPNET will theory model for simulation, came SU in different arrived rate Shi, General wireless network and cognitive wireless network of blocking rate, and Discard rates and throughput data analysis are as follows:SC for unauthorized channels, say3unchanged. SC authorized channel, when SC=2,4,6, SU’s block probability, and drop probability increase and decrease in SC, shows more SC, SU bigger chance of access. As the primary user PU arrival rate increase, SU blocking rate and drop rate increase, because more access led to congestion SU and PU is discarded. As PU service rate of improve, the blocking rate of SU with of fell, because more SU to access; and SU of dropped rate is is in PU has lower service rate Shi has been increased, dang arrived a interval, PU service rate∈[0.02,0.05], SU dropped rate reached maximum value∈ [0.014,0.016], then PU service rate increased, SU dropped rate fell, description PU regardless of when, on SC are has highest using permission. Then, on simulation effect best of SC for at6o’clock of situation in-depth research, found SU of throughput in cognitive wireless network environment in the than General wireless network environment in the good many, because PU of arrived rate increased, SU of available channel on will reduced, so, using SC of user SU throughput will reduced, also; This interupted of SU can select is not is authorized channel SC has free of channel, therefore, the SU can come in interference of situation continues to it of transmission, so the SU and SC throughput than using only authorized channel throughput is better. When we set PC=2,4,6, SC=3, the PU power arrive at different rates, SU blocking rates are low drop rate; PC=2、4、6and SC=0、2、4, the throughput is improvement.