Papers by Keyword: TD-SCDMA

Abstract: The coverage and capacity of high speed data service in coal mine hot spots is not sufficient in present TD-SCDMA communication system. This paper proposes a TD-SCDMA & Wi-Fi network interworking solution , utilizing the high speed data transport of Wi-Fi network on the foundation of TD-SCDMA system. The results show that the solution is feasible and effective .

Abstract: 3G standards such as TD-SCDMA use multi-user detection (MUD) at the base station to combat multi address interference (MAI) and inter-symbol interference (ISI). We review Cholesky factorization and Schur algorithm for Zero Forcing Block Linear Equalization. We compare the solutions of different algorithm for ZF-BLE by computation, and analyze the complexity of those methods.

Abstract: The multi-access interference and quality of communication system can be greatly improved by beam forming technology when the smart antenna is adopted. This paper investigates the performance improvement given by a multi-antenna receiver on a mobile terminal , and a link level simulation scheme is presented based on TD-SCDMA system. The performance of dual smart antenna under different circumstance is analyzed, and three different adaptive algorithms are compared under the specifically modeled multipath fading channel. The simulation results show that a dual-antenna arrangement on a mobile terminal can achieve better performance than a conventional single antenna.

Abstract: With the rapid development of China's TD-SCDMA system, how to qualitative and quantitative to judge intelligent antenna electromagnetic radiation pollution is a problem to be solved. Due to the special working principle of smart antenna, the second generation communication system spectrometer and field intensity meter measurement method is a complicated and difficult to operate. This paper introduces a design suitable for TD smart antenna measurement system: this system can realize in single user or multiple users at the same time and the TD base station set up calls link of multi-point synchronous signal intensity measurement. The measurement results of our system are very close to the measurement results of spectrometer field intensitys and can reasonable reflect TD stations around the extent of the electromagnetic radiation. This method of our system is easy, cheap and maneuverable

Abstract: In this paper, we study the design and development of the system level simulation platform of TD-SCDMA, mainly introducing the design of power control simulation algorithms in multi-carrier cell mode which support mixed service model of UEs. The theory of power control by adaptive integer step-size is described in detail, and the simulation results in TD-SCDMA system level simulation platform with practical examples are analyzed. Taking simulation of power control by our way has certain practical significance.

Abstract: Joint detection (JD) is a core technology of TD-SCDMA system. Only many mathematical models of JD have been proposed and discussed in many references, but there is no a physical model of JD for application. So the concept of JD is not clear. The concept of JD is made clearer by its principle and algorithm with physical model presented in this paper. Also a method for eliminating multi-path interference (MPI) by using mid-amble sequence and frequency spreading code (FSC) would be presented, and a JD constructed by that method would be proposed in the paper.

Abstract: TD-SCDMA system can dynamically allocates time slots between uplink and downlink according to local service requirement, which causes cross-slot interference if adjacent cells have different direction links in the same slot. Because of the specialty of cross-slot interference between base stations, traditional methods which subtract interference in digital baseband don’t work well. A novel method is proposed. Simulation indicates that this scheme can effectively reduce the cross-slot interference.

Abstract: The first interleaving is an effective measure to eliminate long time continuous error during channel coding and multiplexing of TD-SCDMA. In this paper, a circulated cross-connection method is proposed for the first interleaving , and the implemation schedule is designed. The results verified that the method could meet the performance requirement for the first interleaving and is accurate and reliable.

Abstract: Rate-matching is to ensure the transmission channel multiplexed total bit rate to match the physical channel carrying capacity in TD-SCDMA system. It directly affects the quality of sending data. This paper is focused on the researches of rate-matching, the three important parameters is calculated, the rate-matching processing is presented, the computation flow chart is given, and the computation results is listed to demonstrate the influence of semi-static performance on data rate-matching. It provides some basis for the further research of TDD communication.

Abstract: This paper describes a new method to implement frequency offset estimation (FOE) in cell search of the TD-SCDMA system. The received SYNC-DL data is used to calculate frequency offset (FO) before the scrambling code and the Midamble ID is identified. The received Midamble data can be used to calculate FO before Multi-frame synchronization. The FOE with two stages can be used in the same 64chip calculation structure and the hardware resources can be conserved. The simulation results show that the method can control the residual FO within 0.05PPM by smoothing of sub-frame or IIR filtering, which meets the TD-SCDMA system requirements for residual frequency, even though a certain sample bias exist.