Most current Global System for Mobile Communications (GSM) frequency planning methods evaluate the interference and assign frequencies based on measurement reports. Assigning the same or adjacent frequencies to cell...Most current Global System for Mobile Communications (GSM) frequency planning methods evaluate the interference and assign frequencies based on measurement reports. Assigning the same or adjacent frequencies to cells close to each other will introduce co-channel and adjacent channel interference which will reduce network performance. Traditionally, man power is used to check and allocate new frequencies which is time consuming and the accuracy is not satisfactory. This paper presents an intelligent analysis method for optimization of co-channel and adjacent channel interference by exploiting cell configuration information. The method defines an interference evaluation model by analyzing various factors such as the base station layer, the azimuth ward relationship, and the cell neighborhood relationships. The interference for each frequency is evaluated and the problem frequencies are optimized. This method is verified by a large number of actual datasets from an in-service GSM network. The results show this method has better intelligence, accuracy, timeliness, and visualization than traditional methods.展开更多
近年来,北斗导航系统建设逐渐完善,北斗三号区域短报文通信(Reginal Short Message Communication, RSMC)服务已进入行业应用越来越广的关键时期。WiFi信号与北斗三号RSMC出站信号频率接近,在实际使用过程中,2个系统可能存在兼容性问题...近年来,北斗导航系统建设逐渐完善,北斗三号区域短报文通信(Reginal Short Message Communication, RSMC)服务已进入行业应用越来越广的关键时期。WiFi信号与北斗三号RSMC出站信号频率接近,在实际使用过程中,2个系统可能存在兼容性问题。针对WiFi信号干扰对北斗三号RSMC出站信号性能的影响问题,介绍了北斗三号RSMC出站信号的空口特性,分析了WiFi信号对北斗三号RSMC出站信号的带外干扰和带内干扰,基于等效载噪比的分析方法,从载噪比损失方面对干扰的强度做了仿真分析,并给出了改进方法。研究结果为WiFi和北斗区域短报文服务兼容并存提供技术基础。展开更多
为了解决传统邻道干扰模型与测试数据对比误差较大的难题,将接收机射频前端的非线性响应模型和信噪比模型相融合,考虑到邻道干扰信号与本振相位噪声混频而产生的噪声,提出了噪声修正因子,进一步建立了超短波(VHF)电台接收机邻道干扰减...为了解决传统邻道干扰模型与测试数据对比误差较大的难题,将接收机射频前端的非线性响应模型和信噪比模型相融合,考虑到邻道干扰信号与本振相位噪声混频而产生的噪声,提出了噪声修正因子,进一步建立了超短波(VHF)电台接收机邻道干扰减敏模型,与典型实装测试数据相对比误差约为3 d B,表明本文方法能够很好地描述邻道干扰的减敏特性。利用本文模型给出了机载超短波电台邻道干扰评估方法,结合直升机编队飞行时电台邻道干扰评估案例,验证了本文方法的适用性和有效性,具有一定的工程应用价值。展开更多
提出一种在欠采样条件下的经过混合结构设计的射频发射机线性化方法。该方法基于欠采样频率选择性的非线性模型来校正调制器产生的镜像干扰信号以及射频功率放大器的互调失真信号。实验结果表明LTE的70 MHz双载波信号在发射机采样速率从...提出一种在欠采样条件下的经过混合结构设计的射频发射机线性化方法。该方法基于欠采样频率选择性的非线性模型来校正调制器产生的镜像干扰信号以及射频功率放大器的互调失真信号。实验结果表明LTE的70 MHz双载波信号在发射机采样速率从491.52 Ms/s降低至122.88 Ms/s时使用该组合方法较之前方法有10 d B的归一化最小均方误差改善以及10 d B的邻道功率泄露比抑制改善。展开更多
基金Supported by the National Key Projects of Science and Technology of China (No. 2010ZX03005-003)
文摘Most current Global System for Mobile Communications (GSM) frequency planning methods evaluate the interference and assign frequencies based on measurement reports. Assigning the same or adjacent frequencies to cells close to each other will introduce co-channel and adjacent channel interference which will reduce network performance. Traditionally, man power is used to check and allocate new frequencies which is time consuming and the accuracy is not satisfactory. This paper presents an intelligent analysis method for optimization of co-channel and adjacent channel interference by exploiting cell configuration information. The method defines an interference evaluation model by analyzing various factors such as the base station layer, the azimuth ward relationship, and the cell neighborhood relationships. The interference for each frequency is evaluated and the problem frequencies are optimized. This method is verified by a large number of actual datasets from an in-service GSM network. The results show this method has better intelligence, accuracy, timeliness, and visualization than traditional methods.
文摘近年来,北斗导航系统建设逐渐完善,北斗三号区域短报文通信(Reginal Short Message Communication, RSMC)服务已进入行业应用越来越广的关键时期。WiFi信号与北斗三号RSMC出站信号频率接近,在实际使用过程中,2个系统可能存在兼容性问题。针对WiFi信号干扰对北斗三号RSMC出站信号性能的影响问题,介绍了北斗三号RSMC出站信号的空口特性,分析了WiFi信号对北斗三号RSMC出站信号的带外干扰和带内干扰,基于等效载噪比的分析方法,从载噪比损失方面对干扰的强度做了仿真分析,并给出了改进方法。研究结果为WiFi和北斗区域短报文服务兼容并存提供技术基础。
文摘为了解决传统邻道干扰模型与测试数据对比误差较大的难题,将接收机射频前端的非线性响应模型和信噪比模型相融合,考虑到邻道干扰信号与本振相位噪声混频而产生的噪声,提出了噪声修正因子,进一步建立了超短波(VHF)电台接收机邻道干扰减敏模型,与典型实装测试数据相对比误差约为3 d B,表明本文方法能够很好地描述邻道干扰的减敏特性。利用本文模型给出了机载超短波电台邻道干扰评估方法,结合直升机编队飞行时电台邻道干扰评估案例,验证了本文方法的适用性和有效性,具有一定的工程应用价值。
文摘提出一种在欠采样条件下的经过混合结构设计的射频发射机线性化方法。该方法基于欠采样频率选择性的非线性模型来校正调制器产生的镜像干扰信号以及射频功率放大器的互调失真信号。实验结果表明LTE的70 MHz双载波信号在发射机采样速率从491.52 Ms/s降低至122.88 Ms/s时使用该组合方法较之前方法有10 d B的归一化最小均方误差改善以及10 d B的邻道功率泄露比抑制改善。