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Indoor coverage is essential to the mobile user experience, because the signal power from the remote macro base stations is seriously weakened after penetrating the walls. Traditional indoor coverage system is a good solution but it can not be deployed in all the buildings. In order to enhance the received signal power inside the building, a relay can be used in a long term evolution (LTE) system. The benefits of relay are: it can be deployed anywhere quite near to the building since it uses wireless backhaul with less position limitation, and thus it can amplify the transmitting power due to the nearby position to the building comparing to the remote macro base stations. Then even with penetration loss, the received signal power inside the building is still high enough to carry traffic. The field test results show that a TD-LTE relay can improve the indoor received signal power and traffic obviously, and thus it's a good solution to enhance outdoor to indoor coverage.

Calculates the envelope thermal characteristics of the Phase Change Material (PCM) lightweight building fabrics, such as the thermal inertia index, storage heat coefficient, delay time and attenuation ratio,ect. Comparing with the common lightweight building fabric the envelope thermal characteristics of the PCM lightweight building fabrics has been improved preferably. The thermal inertia index, attenuation ratio and delay time of PCM components are respectively the 3.75,14 and 10 times as the one of the common building fabrics. So, it will be less cooling load in the PCM lightweight building than the common lightweight building. Then combining the nighttime ventilation we carries through the contrast experiments between light weight PCM wall and ordinary building in chongqing summer, the results show that the electricity consumption in light weight PCM wall room be 32.5% less than the one in ordinary room, the results also show that outdoor temperature have great effect on the energy efficiency.

To master the heat transfer rule of phase change material(PCM) wall, two kinds of hollow boxes was made with different material, one was made of pure EPS granule，the other one was made of EPS and PCM, temperature of cavum was measured during thermal translation process experiment. The hollow boxes was separated into 4 nodes finite element, the experiment time was divided into finite time point, the diathermanous process of boxes was simulated by finite element software system. The result indicated that simulation process by computer was inosculated with experiment, there was obvious temperature flateform during heat transfer of PCM wall, duration of different direction of phase change process was different, during ascendant process and descent process, change rate and distributing characteristic were contrary on the two sides of phase change point temperature.

In this paper, the impact of diversity order on symbol error rate (SER) performance is investigated for the cooperative amplify-and-forward (AF) multiple-input-and-multiple-output (MIMO) relaying system under the average power scaling (APS) constraints. Furthermore, the optimal power allocation (OPA) scheme is proposed based on the criterion of maximizing signal-to-noise-ratio (SNR). Through the SER analysis and numerical results, it can be shown that the diversity order in AF MIMO relaying system under APS is MT (the number of transmitting antennas) when uniform power allocation (UPA) is adopted. Given MR receiving antennas at the relay nodes, the proposed novel OPA scheme can not only reduce the SER but also improve the diversity order efficiently up to MR even when MT = 1.

Relay is emerged recently as a promising solution not only to improve coverage but also end-to-end date rate. How to manage the radio resources effectively for the integrated cellular network are the key issues to be studied. The paper re-evaluates the traditional concept of adjustment and optimization for the call routing and congestion control as call routing and admission control (CRAC). With respect to the mobility and the variable wireless environment, the call re-routing algorithm which implements the intelligence and adaptability is also studied as call re-routing control (CRRC). The joint routing and re-routing control (JoRR) algorithm is proposed to realizes the global optimization of the existing algorithms Two schemes, namely Centralized Architecture (CA) and Decentralized Architecture (DA), are studied to implement the JoRR algorithm whose criterion is selected by considering the characteristics of the integrated cellular system and the tradeoff between the cost and the effectivity. At last, a set of system-level performance evaluation is provided based on the characteristics of the new network architecture.

In future wireless communication systems, an architecture introducing wireless relaying technologies into the cellular infrastructure, seems a promising approach to enlarge the coverage area and enhance system capacity. How to design an efficient call admission control algorithm to perform routing and channel allocation for such integrated cellular system, and manage the radio resources effectively are the key issues to be studied. Based on time division multiple access (TDMA) scheme, this paper proposes a novel call routing and admission control (CRAC) algorithm for the two-hop cellular system with the aim of extending system coverage and increasing system capacity cost-effectively. With the proposed CRAC algorithm, a mobile terminal (MT) can choose the conventional direct link or opt for the relaying considering the transmission quality as well as the traffic load balance. The simulation results show that the CRAC algorithm can decrease the blocking probability significantly and increase the system capacity and enhance the coverage by utilizing the limited channel resource efficiently. Keywords-Relaying, Call routing and admission control (CRAC), Cellular

The multiple input multiple output (MIMO) system is a huge reform to future wireless communication systems. The proposed MIMO-based virtual group cell structure is a novel cellular construction method, which is suitable for new advanced physical techniques. However, existing radio resource management algorithms are not suitable for multiple antenna environments. The paper improves the traditional admission control algorithm and makes it suitable for MIMO systems. According to the characteristics of the new network architecture, a different interference distribution model is provided to help evaluate the system performance.