Improved H-infinity channel estimator based on EM for MIMO-OFDM systems

来源 :Journal of Systems Engineering and Electronics | 被引量 : 0次 | 上传用户:skjthit
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
H-infinity estimator is generally implemented in timevariant state-space models,but it leads to high complexity when the model is used for multiple input multiple output with orthogonal frequency division multiplexing (MIMO-OFDM) systems.Thus,an H-infinity estimator over time-invariant system models is proposed,which modifies the Krein space accordingly.In order to avoid the large matrix inversion and multiplication required in each OFDM symbol from different transmit antennas,expectation maximization (EM) is developed to reduce the high computational load.Joint estimation over multiple OFDM symbols is used to resist the high pilot overhead generated by the increasing number of transmit antennas.Finally,the performance of the proposed estimator is enhanced via an angle-domain process.Through performance analysis and simulation experiments,it is indicated that the proposed algorithm has a better mean square error (MSE) and bit error rate (BER) performance than the optimal least square (LS) estimator.Joint estimation over multiple OFDM symbols can not only reduce the pilot overhead but also promote the channel performance.What is more,an obvious improvement can be obtained by using the angle-domain filter. H-infinity estimator is generally implemented in time-variant state-space models, but it leads to high complexity when the model is used for multiple input multiple output with orthogonal frequency division multiplexing (MIMO-OFDM) systems.Thus, an H-infinity estimator over time-invariant system models is proposed, which modifies the Krein space accordingly. In order to avoid the large matrix inversion and multiplication required in each OFDM symbol from different transmit antennas, expectation maximization (EM) is developed to reduce the high computational load. Joint estimating over multiple OFDM symbols is used to resist the high pilot overhead generated by the increasing number of transmit antennas. Finally, the performance of the proposed estimator is enhanced via an angle-domain process. Through performance analysis and simulation experiments, it is indicated that the proposed algorithm has a better mean square error (MSE) and bit error rate (BER) performance than the optimal least square ( LS) estimator.Joint estimation over multiple OFDM symbols can not only reduce the pilot overhead but also promote the channel performance. What is more, an obvious improvement can be obtained by using the angle-domain filter.
其他文献
目的了解HIV感染者/AIDS患者生存质量,分析相关影响因素,为探索艾滋病防治与救助模式提供有益借鉴。方法采用方便抽样方法选取在巴南区接受检测、治疗的HIV感染者/AIDS患者进
通过阐述矿区发展面临的问题,根据循环经济的理论内涵,分析矿区发展循环经济的优势所在;在矿区循环经济模式的初步实践基础上,探讨发展生态旅游、构建生态网链、推进科技创新
白洋淀区域在历史发展过程中形成了一系列历史底蕴深厚、形态丰富的历史城镇,对其形态特征与影响因素进行研究,可以为建设雄安新区提供科学参考.本文收集明、清、民国、建国
我主要谈谈自己这些年来思考的三个观点:第一、力量重于财富;第二、制度重于技术;第三、政策重于投入.rn第一个观点:力量重于财富.今天对于一国经济来说最重要的已不是规模而
我国幅员辽阔,地质地貌条件复杂,同时也是一个多山的国家,每年发生的地质灾害给国民经济造成了重大的损失,为此,加强和完善地质灾害的监测技术成为了当务之急.文中论述了地质
患者女,31岁。妊娠38周检查梅毒血清试验RPR 1∶16(+),TPPA(+),皮肤科检查未发现皮损,未触及皮下肿大的淋巴结。诊断:妊娠隐性梅毒。分娩后复查RPR(-),TPPA(+)。认为患者系因
1 临床资料rn患者男,18岁.周身反复出现鳞屑性红斑伴瘙痒3年.3年前,无明显诱因患者全身出现大小不等的红斑和丘疹,上覆鳞屑,自觉瘙痒,后皮损面积逐渐增大,形成斑块状,多家医
期刊
1临床资料患者男,70岁。左侧颌下淋巴结肿大40d。40d前,患者左侧颌下摸到一樱桃大肿物,挤压后伴有疼痛,当地诊所以“淋巴结炎”静滴头孢类抗生素(具体用药不详),无效,肿物仍
期刊
1998年南海的中、北部海温比多年同期的平均值偏高1~2℃,属于历史上少数几个偏暖的年份之一.1998年5月的实测降雨量分布).由图2可见,广东的中部、南部和西南部的大部分地区月
会议
患者男,37岁,全身泛发丘疹2年。皮肤科情况:头面部、颈部、躯干、双上肢、生殖器部位可见近百个半球形丘疹,丘疹表现为正常肤色,部分丘疹中央有脐凹。面部丘疹行皮损病理检查