Research On The Indoor Wideband Radio Channel Measurements And Modeling

With the development of mobile communication key technology such as MIMO, OFDM and the evolution of mobile communication standards, mobile communication system can provide increasing high voice quality and data transmission rate. On the other hand, with the market promotion of intelligent terminals, wireless data traffic in the indoor environment increased significantly, and this requires a higher quality of wireless communication. However, the wireless channel condition is a very important factor to constraint the system performance and quality of wireless communication. Research on radio channel plays an important role for the communication system, which provides reference for wireless network planning, communication system design, test, simulation and selection of key technology. In this condition, this paper mainly investigates the indoor and corridor radio channel measurements and channel modeling at900MHz and1800MHz.Firstly the basic theory of broadband radio channel measurement and methods of channel modeling are studied in this paper. Conditions of sounding signal and measurement system are analyzed and methods of channel measurement such as periodic pulse sounding method, sliding correlation method and frequency domain measurement method are compared. Based on the sliding correlation method, the channel measurement system is set up using the vector signal generator and FSQ signal analyzer. Channel measurements in10different indoor and corridor propagation scenarios are taken according to different frequency and distance of transreceiver. Data processing and analysis methods are proposed considering the measuring system performance and background noise.Secendly, the characteristics, modeling theory and modeling methods of wideband radio channel are investicated in this paper, variation of power delay profile (PDP) and root mean square (RMS) delay spread in different scenarios are analyzed, the number, delay and power of multi-path in each scenario are derived from PDP, and at last, universal channel models for indoor and corridor environment are proposed.The innovative work in this paper is as follows:I. An improved sliding correlation method is applied in this paper, the computer at the receiver side generates exactly the same pseudo-random noise (PN) sequence as the transmitter side, the sliding correlation process is moved to the computer from the traditional receiver, which reduces the complexity of the receiver and improves the accuracy of data processing. What’s more, coherent reception technology of I/Q path adopted in the receiver can detect multipath amplitude as well as phase information.Ⅱ.The radio propagation characteristics are analyzed based on the test data in corridor scenario, which is a very special environment. The variation of multipath structure and RMS delay spread are studied in conditions of different frequency, different distance of transreceiver and existence of line-of-sight (LOS) path or not, and some important conclusions are drawn according to the analysis.III. Wideband channel models for indoor environment, such as laboratories, offices, meeting rooms, and typical corridor environment are proposed in this paper.