Time Division-Synchronous Code Division Multiple Access (TD-SCDMA),a home-grown standard for the third generation mobile communications,is already mature and ready for commercial deployment. The enhancement and evolut...Time Division-Synchronous Code Division Multiple Access (TD-SCDMA),a home-grown standard for the third generation mobile communications,is already mature and ready for commercial deployment. The enhancement and evolution of the TD-SCDMA system is a hot topic recently. Many strategies for TD-SCDMA enhancements and evolutions have been proposed,but there are no integrated solutions that can jointly consider the development both in the short term and in the long term. This paper discusses four evolution phases,which are proposed according to the key technologies. Phase 1 is about the current TD-SCDMA system. Phase 2 is the short term evolution of TD-SCDMA,i.e.,the period of HSxPA,including the evolution of High Speed Downlink Packet Access (HSDPA),High Speed Uplink Packet Access (HSUPA) and High Speed Packet Access plus (HSPA+). Phase 3 is the Long Term Evolution (LTE). Phase 4 is the Beyond 3G (B3G)/Fourth Generation (4G) mobile communication Time Division Duplex (TDD) system,which is based on TD-SCDMA. Key characters for every evolution phase are discussed,as well as the advanced technologies adopted in the evolution process such as Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM).展开更多
In this paper, a simple method is presented for multi-user space-time channel estimation in Time Division-Synchronized Code Division Multiple Access (TD-SCDMA) systems. The method is based on a spe- cific midamble ass...In this paper, a simple method is presented for multi-user space-time channel estimation in Time Division-Synchronized Code Division Multiple Access (TD-SCDMA) systems. The method is based on a spe- cific midamble assignment strategy, which results in a cyclic Toeplitz midamble-matrix in the linear equation of the received data vectors. A Fast Fourier Transform (FFT)-based algorithm is used to obtain the estimate of the uplink multi-user space-time channels. Furthermore, the estimated space-time channel is applied to the identification of multi-paths for each user, and Direction Of Arrival (DOA) estimation for each path is carried out by using the extracted spatial signature vector. Aside from the simplicity in computation, the proposed di- rection of arrival estimation method can effectively resolve multi-paths regardless of the correlation and angle separations of the multi-paths.展开更多
基金the 863 Program of China under grant 2006AA01Z257the National Natural Science Foundation of China under grants 60602058 and 60572120.
文摘Time Division-Synchronous Code Division Multiple Access (TD-SCDMA),a home-grown standard for the third generation mobile communications,is already mature and ready for commercial deployment. The enhancement and evolution of the TD-SCDMA system is a hot topic recently. Many strategies for TD-SCDMA enhancements and evolutions have been proposed,but there are no integrated solutions that can jointly consider the development both in the short term and in the long term. This paper discusses four evolution phases,which are proposed according to the key technologies. Phase 1 is about the current TD-SCDMA system. Phase 2 is the short term evolution of TD-SCDMA,i.e.,the period of HSxPA,including the evolution of High Speed Downlink Packet Access (HSDPA),High Speed Uplink Packet Access (HSUPA) and High Speed Packet Access plus (HSPA+). Phase 3 is the Long Term Evolution (LTE). Phase 4 is the Beyond 3G (B3G)/Fourth Generation (4G) mobile communication Time Division Duplex (TDD) system,which is based on TD-SCDMA. Key characters for every evolution phase are discussed,as well as the advanced technologies adopted in the evolution process such as Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM).
基金Supported by the Natural Foundation of Hubei Province, China (No.2005ABA224).
文摘In this paper, a simple method is presented for multi-user space-time channel estimation in Time Division-Synchronized Code Division Multiple Access (TD-SCDMA) systems. The method is based on a spe- cific midamble assignment strategy, which results in a cyclic Toeplitz midamble-matrix in the linear equation of the received data vectors. A Fast Fourier Transform (FFT)-based algorithm is used to obtain the estimate of the uplink multi-user space-time channels. Furthermore, the estimated space-time channel is applied to the identification of multi-paths for each user, and Direction Of Arrival (DOA) estimation for each path is carried out by using the extracted spatial signature vector. Aside from the simplicity in computation, the proposed di- rection of arrival estimation method can effectively resolve multi-paths regardless of the correlation and angle separations of the multi-paths.
