Applied Mechanics and Materials Vols. 195-196

Abstract: This paper proposed a relay sharing and soft frequency reuse based (RSSFR) frequency planning scheme, which reaches high data rates while using the precious frequency resource efficiently, system performance is analysed and evaluated as well. System performance is enhanced in four aspects: 1) Co-channel interference is reduced significantly, which broadens the area of high achievable data rates in each cell. 2) Base stations (BSs) communicate with fixed relay stations through narrow beam antennas, which boosts the resource efficiency without bringing much interference to mobile stations (MSs). 3) The relay sharing strategy can not only bring down network cost, but also provide a better coverage to cell edge users. 4) Soft frequency reuse on shared relay increases the frequency resource efficiency further. Simulation results show that, a better tradeoff between cell throughput and frequency resource efficiency is achieved in RSSFR.

Abstract: This paper presents a method of mobile acoustic source positioning system in the realization of intelligent car localization with the only acoustic signal available. This system consists of intelligent car, sensors and MCU. And it is not limited with the intensity of light using only acoustic signal to realize its auto-controlled localization. This system has merits like simplicity, low cost and low power consumption, and it can be applied in the voice positioning robotic technology.

Abstract: Cognitive Radio is an intelligent radio that should be adapted to the time-varying environment. However, an adaptive fusion rule has been investigated by a rather limited work. In this paper, we present a new approach which is derived from the inspiration of human learning mechanism based on conditioning in behavioural theory. The framework and algorithmic flow are introduced. Moreover, the proposed method is proven to perform well in the dynamic circumstance by the result of the simulation.

Abstract: The demand of high-speed communication leads that the application for resource of channel exceeds the range of linear model. The channel should be described as a nonlinear model. So, the paper uses the adaptive neuron-fuzzy inference system (ANFIS) to identify and equalize the nonlinear channel of the high-speed communication system. Meanwhile, the subtract cluster is applied to identify the construction of the ANFIS and the hybrid learning algorithm based on the least square and back-propagation is used to train network. The simulation results show that the convergence rate and identification accuracy of the ANFIS are better than BP network and the efficiency of the ANFIS based on subtract cluster partition algorithm is higher than that of the ANFIS based on the grid partition algorithm.

Abstract: A macromodel of the prototype of memristor is developed in Advance Design System software (ADS) by using symbolically defined devices (SDDs). This model can simulate the electrical behaviors of a memristor. It is shown that the presented macromodel meets the requirements for simulations of application circuits.

Abstract: sup>2C serial bus is one kind of simple double-lines bus which is developed for effective control between the electronic devices by the Philips Corporation. In this paper, I²C bus structure, specialty and working theory are described, and the bus signal type, wave figure are provided. We Provides the usage of I²C bus on the mobile phone and illuminate how I²C manage the module on the mobile phone to realize the module operate and make the phone work. With Pearl and Onyx phone as a sample, we describe the I²C bus and the related circuit components' importance to the phone. Any change on the components of I²C circuit can provide big variance to the phone performance.

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.

Abstract: Detection is a major challenge for the utilization of multiple-input multiple-output (MIMO) system. Even the fixed sphere decoding (FSD), which is known for its simplicity in calculation, requests too much computation in high order modulation and large number antenna system especially for mobile battery-operated devices. In this paper, a reduced FSD algorithm is proposed to simplify the calculation complexity of the FSD while maintaining the performance at the same time. Simulation results in a 4×4, 16-QAM system show that up to 89% calculation can be saved while the performance drop is less than 0.1dB when SNR=24.

Abstract: A new method is proposed for blind parameter estimation of frequency hopping signals. According to the relation between peaks location on the time frequency plane and component centers of frequency hopping signals, parameter estimation problem is solved using multi-species particle swarm optimization algorithm. Each particle moves around the time and frequency plane and will converge to different species, which species seed represents the center of frequency hopping component. Using this method, the parameters of frequency hopping signals can be estimated. Simulation results demonstrate that the method is effective and feasible.

Abstract: This paper proposes a novel greedy user ordering algorithm for the multiuser multiple-input multiple-output (MIMO) systems employing block diagonal geometric mean decomposition method and Tomlinson-Harashima precoding (THP). Theoretical analysis and computer simulations illustrate its low computation complexity relative to the optimal user ordering achieving by brute search over all the possible ordering permutations resulting in extremely high computation complexity. Meanwhile the bit error rate (BER) performance of the proposed algorithm is very close to the optimal user ordering. Moreover, in order to mitigate the impact of users with smaller sub-channel gains to the whole systems BER performance, a joint pre-processing scheme design of adaptive data streams reduction and greedy user ordering (ADSR-GUO) is proposed. By means of choosing different values for the controlling factor, we can obtain different system sum-rate and BER performance to satisfy different quality-of-service (QoS) requirements.