远近效应

在DS/CDMA系统中，采用多用户检测技术可以有效地克服多址干扰（MAI，MultipleAccessInterference）及远近效应。

In DS / CDMA system , the multiuser detection technique is used to remove the Multiple Access Interference ( MAI ) and resist near-far effect .

环形OCDMA系统中远近效应的研究

Research on Near-far Effect in the Ring OCDMA System

mW复合序列在扩频通信中抗远近效应的应用

Implementation of resisting near-far effects of MW composite sequence in spread spectrum system

在码分多址（CDMA）移动通信系统中，反向链路功率控制对克服“远近效应”和增加系统容量是非常重要的。

Power control is of paramount important to combat the near-far problem and achieve high system capacity in CDMA cellular system .

一种新的抗远近效应的盲DS-CDMA接收机

A New Near Far Resistant Blind DS CDMA Receiver

本文讨论的就是这两种技术的结合，用智能天线技术来解决CDMA系统中存在的诸如多址干扰、远近效应问题。

The article combined the two technologies and used smart antennas to solve problems in CDMA system such as multi-access interference and near-far effect .

本文以问答的形式，就目前消费者关心的一些问题，例如峰值发射功率、远近效应、如何打IP电话等作了剖析。

Some questions that user concerned about were answered in the form of Q & A , including peak emission power , distance effect , how to use IP phone , etc.

近看远观：中国燃料油市场何去何从？环形OCDMA系统中远近效应的研究

A View of China s Fuel Oil Market ; Research on Near-far Effect in the Ring OCDMA System

仿真和信噪比分析都表明，该方法有较好的抗“远近效应”能力，适合GPS伪卫星导航系统应用。

The result of simulations and theoretical analysis of SNR demonstrate that this method has a great capability to resist the near far problem and can be widely used in GPS pseudolite navigation system .

由于采用了这种前向差错控制（FEC）信道编码技术，使得CDMA系统具有了较好的抗远近效应性能。

The CDMA system attains the better performance of resisting near-far effective because of employing this forward error control ( FEC ) channel coding technology .

根据差分GPS原理，分别从影响定位精度的三个方面：时间同步、远近效应、几何精度衰减因子予以讨论。

According to the principle of DGPS , separately discusses the problem in three aspects which is influenced position accuracy , that is time synchronization , near-far effect , geometric dilution of precision ( DOP ) .

从而实现消除MAI和ISI，缓解远近效应问题，从而彻底改善系统性能，提高系统容量。

In order to achieve elimination of MAI and ISI , mitigate near-far problem , thus thoroughly improve the system performance , increased system capacity .

码分多址（CDMA）系统是一个干扰受限系统，系统中存在多址干扰和远近效应，这两种因素是限制CDMA系统容量的主要因素。

Code Division Multiple Acess ( CDMA ) is a self-interfered system , where multiple access interference ( MAI ) and near-far effect existing as the main factors restricting CDMA system capacity .

同其它CDMA系统一样，TDDCDMA系统在无线传输中仍然存在着多径衰落、时延扩展、远近效应、多址干扰等问题，直接影响了系统的容量和服务质量。

But in TDD-CDMA system , there are many problems to solve including multipath fading , perspective effect , multiple access interference which influence its capacity and quality of service .

在CDMA通信系统中，信道参数的估计，特别是信号传输时延的估计是一个重要问题，但是在异步CDMA通信系统中，传输时延和幅度的估计会受到远近效应的影响。

Channel estimation is very important in CDMA communication systems . However , in asynchronous CDMA communication systems the channel estimation of the multipath signals will be degraded by the near far effect .

功率控制是CDMA系统的关键技术之一，它不仅能够克服远近效应，更重要的是能够减少用户间的多址干扰从而提高系统容量。

Transmission power control is one of the key techniques in CDMA systems . It can solve the " near-far problem " and reduce the Multiple-Access Interface ( MAI ) thus improve the system capacity greatly .

仿真结果表明，无论是抗多址干扰还是抑制远近效应，自适应BP神经网络接收机都明显优于传统接收机和BP神经网络接收机，其性能非常接近最佳接收机。

The results show that whether the resistance to multiple access interference or the robust to near far effects , the proposed receiver significantly outperforms not only the conventional receiver but also BP networks receiver and is comparable to the optimum receiver .

该文提出了一种基于TDMA信号体制下的方波调制方案，该方案既解决了远近效应，又避免了在较高的中频上采用过高的系统时钟。

The paper presents a square wave modulation scheme based on TDMA signal system to resolve the problem . Also it can avoid the high speed system clock .

首先，发现MMSE多用户检测器可以有效抑制CDMA系统的远近效应，进而降低CDMA系统对功率控制的依赖。

Firstly , it is found that the MMSE multiuser detector can constrain the near-far effect in a CDMA system , therefore reduce the requirements of the power control in the CDMA Ad hoc networks .

分析和仿真结果表明，无论是在多址干扰还是在非Gaussian脉冲噪声占主导的情况下，EM/SAGE-MUD算法在降低误码率，克服远近效应方面比起传统的多用户检测方法有显著改善。

Analytical and simulation results show that the technique is robust with wider applicability than conventional multiuser detectors in terms of near-far resistance and bit error rate ( BER ) when either MAI or non-Gaussian impulsive noise is dominant .

它不仅可以消除多址干扰，还能有效地解决远近效应和码间串扰问题，降低系统对功率控制的要求，提高了CDMA系统的容量。

It is not only resistant to MAI , but also effectively solves Near-far Effect and the problems of inter-symbol interference , lowers the requirement of system to power control , and increases the capacity of CDMA system .

其中，功率控制是WCDMA系统中消除远近效应和边缘效应、减少系统内移动用户间干扰以及提高系统容量的关键技术之一。

Especially , the power control as one of the key technologies in WCDMA system can eliminate the edge effect and the distance effect , reduce the system interference , and enhance the system capacity .

在移动通信系统中，传输功率控制是抑制共道干扰、克服远近效应、降低功率消耗、增加系统容量的重要手段，现已成为第三代（3G）移动通信系统的关键技术之一。

Transmitter power control has been proven to be an important means in suppressing co-channel interference , combating near-far problem , lowering power consumption and increasing systems capacity . It has been one of the key technologies in 3G mobile communication systems .

功率控制是无线通信不可缺少的一部分，也是CDMA系统的关键技术之一，它有效的调整了移动用户和基站的发射功率、补偿信道衰落、消除远近效应，维持了链路的高效通信。

Power control is the key part of the wireless communication , as well as the important strategy in CDMA system , which not only adjusts transmit power of the mobile station and base station but also compensates channel fading and counteracts near-far effect .

实验2a的结果表明：时间距离表征有助于读者对目标进行持续的追踪；未达成目标促进了信息的整合，并削弱了时间距离的远近效应。

The results of experiment 2a showed : the representation of temporal distance conduced to tracking the goal continuously ; uncompleted goal aided integration of the text information , and weakened the far-close effects of temporal distance .

由于CDMA是一个自干扰系统，存在严重的多址干扰及远近效应问题，制约了CDMA的性能和容量，多用户检测作为宽带CDMA通信系统中的抗干扰的关键技术受到广泛的重视。

But because CDMA is a self-interference system , there exist severe MAI and near-far problem which reduce the performance and capacity of CDMA . Great importance has been continuously attached to multiuser detection , one of the key techniques for wideband CDMA communications systems .

为了对抗多址干扰和远近效应，研究将RBF（经向基函数，Radialbasisfunction）神经网络中的递归正交最小二乘（ROLS-AWS）算法应用于多用户检测中。

In order to suppress the multiple access interference ( MAI ) and resist near-far effect , the recursive orthogonal least square with auto weight selection ( ROLS-AWS ) algorithm used in radial basis function ( RBF ) neural network is introduced to the multiuser detection ( MUD ) .

将Walsh函数序列与直接扩频序列相结合构成的DS-FH混合扩频通信方式对于系统抗多址干扰和远近效应具有重要意义。

Combining Walsh sequence with direct spread spectrum sequence , we can construct hybrid DS-FH spread-spectrum communication mode . This is very important for the mode to have better performance on anti-multiple-access inference and anti-near-far inference .

仿真结果证明了ICSA检测器能够快速收敛到全局最优解，并且无论抗多址干扰和抗远近效应能力都优于传统方法和一些应用优化算法的多用户检测器。

Simulation results show that the proposed detector not only can achieve the global optimization values in fast convergence rate , but also is superior to the conventional receiver and the multiuser detectors based on the previous optimal algorithms in the cancellation of multiple-access-interference and near-far effect .

作了在有远近效应情况下的性能比较。

The performance comparison under the effects of near-far is also investigated .