分组预约多址（PRMA）的性能仿真

本文首先给出了分组预约多址（ＰＲＭＡ）的定义和基本性能，然后通过计算机仿真的方法，分析了话音统计特性对ＰＲＭＡ性能的影响。结果表明ＰＲＭＡ系统容量对话音通信过程中的平均有声期的长度变化不敏感，而对话音通信过程中话音激活因子的变化非常敏感。     

冲突消弱分组预约多址协议及其性能分析

本文讨论了分组预约多址接入（ＰＲＭＡ）协议的缺点,提出了一种突消弱分组预约多址接入（ＣＲ－ＰＲＭＡ）协议,理论分析和计算机仿真均表明ＣＲ－ＰＲＭＡ的性能优于ＰＲＭＡ。     

一种基于服务质量(QoS)的分组预约多址协议

本文从用户角度和实际通信情况考虑,提出了一种基于服务质量的分组预约多址协议（ＥＴ－ＰＲＭＡ）。该方法利用用户信息之间的相关性,适当地调整分组预约多址（ＰＲＭＡ）协议中的话音用户再次竞争信道的概率,提高ＰＲＭＡ系统中话音终端获取信道的速度,从而达到提高话音业务性能,从计算机仿真的结果看,该方法对提高ＰＲＭＡ系统中话音业务的性能确有帮助。     

改善分组预约多址协议中话音业务性能的一种方法

本文在分析分组预约多址（ＰＲＭＡ）协议的基础上,从用户角度和实际通信情况考虑,提出了基于补偿性参数作为系统的性能参数,并采用适当加大用户再次竞争信道的允许概率来提高ＰＲＭＡ系统中话音业务性能的方法（ＶＰ－ＰＲＭＡ）,从计算机仿真的结果看,该方法对提高ＰＲＭＡ系统中话音业务的性能确有帮助。     

第三代移动通信系统中一种多址接入方案的性能分析

对一种多址接入方案—联合ＣＤＭＡ／ＰＲＭＡ方案在单纯话音业务、混合话音和数据业务以及混合话音和图像业务情况下分别进行计算机模拟并分析结果，得出其性能优于单纯ＣＤＭＡ方案的结论。     

无冲突话音/数据综合业务分组预约多址(CF-IPRMA)协议及其性能

本文提出了无冲突话音／数据综合业务的ＰＲＭＡ协议：ＣＦ－ＩＰＲＭＡ协议,并利用马尔可夫链模型法,对ＣＦ－ＩＰＲＭＡ协议中的数据通信性能进行了分析;分析结果表明,该协议在保证话音通信质量的前提下,具有较高的数据业务通过率。     

分组预约多址协议在DECT系统中的应用

提出了将ＰＲＭＡ协议应用于ＤＥＣＴ,实现ＤＥＣＴ／ＰＲＭＡ系统的方案,分析和仿真表明,ＤＥＣＴ／ＰＲＭＡ系统可以大幅度提高系统的容量,同时也易于实现。     

PRMA／TDD多址协议下的数据—话音综合

本文提出了一个在ＰＲＭＡ／ＴＤＤ多址协议下的数据－话音综合方案，该方案以动态边界分离话音和数据业务。动态边界的位置由话音子系统的业务负荷确定，使系统在保证话音业务质量的前提下，让数据业务获得最大带宽，通过马尔可失链建模，推导出了数据业务最大化公式，并进行了计算机系统仿真。分析结果表明，与ＰＲＭＡ数－话综合方案相比，该方案可使系统性能明显提高。动态边界也使话音业务子系统独立于数据业务子系统，因此，数     

无冲突NC—IPRMA协议下的数据——话音综合

提出了一个面向微蜂窝通信的支持数据－－话音综合业务的无冲突分组预约多址协议－－ＮＣ－ＩＰＲＭＡ协议,通过Ｍ／Ｍ／Ｎ∞／Ｍ,排队模型分析了ＮＣ－ＩＰＲＭＡ协议的话音子系统性能,通过系统仿真分析了数据－－话音综合性能。研究结果表明,在支持数据－－话音综合业务方面,ＮＣ－ＩＰＲＭＡ协议比ＰＲＭＡ和ＩＰＲＭＡ协议更高效,这包括更高的认道利用率,更短的数据分组时延和更大的话音终端容量。由于采用排队等待方式接     

具有随机到达时间的扩频PRMA及其性能分析

本文首先提出了一种称为具有随机到达时间的扩频多址协议，然后用马氏链分析方法分析了该协议的信道利用率及话音分组丢失率，给出了于个计算分级 失率的公式，如果把每一时隙时址码的数目定为１，这个公式也可同样用于ＰＲＭＡ分组丢失率的计算，这是文献「４」中没有解决的问题，我们利用了延时捕获得现象来改进该协议的性能，在理论分析及模拟中，我们也考虑了分组传输错误对协议性能的影响，理论分析及模拟结果均瞎时捕获得现象     

Packet reservation multiple access in a metropolitan microcellularradio environment

The author examines the performance of a packet reservation multiple access (PRMA) protocol in a metropolitan microcellular radio environment using computer simulations. Call characteristics, mobility, and channel conditions have an impact on PRMA performance which is measured in terms of the average packet dropping rate per call. In order to maintain a reasonable level of service quality for calls in progress, teletraffic loading can be controlled by introducing a call setup queue and limiting the number of active subscribers. Call mobility is found to have a minor impact on PRMA performance. PRMA is also fairly robust against adverse channel conditions with a drop in performance of about 15% when the channel packet loss rate is less than 0.01. Performance comparisons to other protocols are also carried out     

时分双工环境下的分组预约多址(PRMA/TDD)协议及其性能

在分析标准分组预约多址（PRMA／FDD）协议的基础上,提出了时分双工环境下的分组预约多址（PRMA／TDD）协议,理论分析和计算机仿真均表明,PRMA／TDD与PRMA／FDD的性能相近,可以较大幅度地提高系统的容量。     

Handoff effect on packet reservation multiple access (PRMA) in microcellular system

Packet reservation multiple access (PRMA) has been proposed for third-generation wireless information networks by D.J. Goodman and S.X. Wei (see ibid., vol.40, p.170-6, 1991). The mobile-initiated handoff has been proposed to disperse the base station (BS) burden, which is increased by the small microcell radius. However, increased contentions, due to handoff, affect the overall performance of PRMA, even though these frequent handoffs do not burden the BS. We analyze the handoff effect on PRMA performance under a microcellular system, both voice-only and combined voice-and-data systems. A steady state voice-terminal model with handoff is proposed. System-equilibrium equations are derived using the proposed model. The system performance is evaluated, using a Markov analysis method, in terms of packet-dropping probability, data-packet delay, and throughput. The change of performance under handoff show the impact of handoff on PRMA.     

Numerical analysis of joint CDMA/PRMA protocol based on equilibriumpoint analysis

Numerical expressions to assess the performance of a joint direct sequence code division multiple access/packet reservation multiple access (CDMA/PRMA) protocol are presented. Simulation of CDMA/PRMA systems with narrowbeam antennas is also applied to support the proposed technique     

卫星通信系统中的多址接入协议

简述了卫星通信中多址协议的分类和影响多址协议性能的因素,重点介绍了三种预约多址协议PRMA-HS、PRMA/CDMA和Butst Reservation CDMA,并分析了它们的性能.     

Performance Investigation of CDMA/PRMA with Imperfect Power Control in TDD Cellular Systems

This study investigates the performance of joint code-division multiple access/packet-reservation multiple access (CDMA/PRMA) with the consideration of imperfect power control in TDD-CDMA cellular systems, and compares with that of CDMA/PRMA with an assumption of perfect power control. Both voice and World Wide Web (WWW) Internet browsing traffic were considered. We have studied their performances in terms of packet loss probability, power outage probability and average access delay. The results show that the assumption of CDMA/PRMA with perfect power control is too optimistic and independent of cell radius. It might be valid when the cell radius is <500 m. In addition, the performance of CDMA/PRMA with imperfect power control is highly limited by the cell radius due to its constraint on transmission power levels. Therefore, careful study is required if CDMA/PRMA is used in TDD systems.     

Performance simulation of NC-PRMA with signatures in microcellular communication systems

Packet reservation multiple access (PRMA) improves capacity in microcellular systems compared with time division multiple access (TDMA) or frequency division multiple access (FDMA). In PRMA, when a mobile terminal has information packets to transmit, it contends with other terminals for access to a common radio channel. Therefore the main performance degradation is due to the collision of terminals simultaneously transmitting packets. In this paper we propose a non-collision PRMA (NC-PRMA) protocol with signatures to achieve a better performance than PRMA does. Two classes of duplexing schemes, frequency division duplexing (FDD) and shared time division duplexing (STDD), are explored and two speech activity models, slow and fast, in both FDD and STDD schemes are studied. From the results of a computer simulation it is observed that, with the constraint of a packet-dropping rate no greater than 0·01, NC-PRMA can support 38 (43) and 45 (49) users respectively under the FDD and STDD schemes if the slow (fast) speech activity detector is adopted. © 1998 John Wiley & Sons, Ltd.