ABSTRACT
Chambers ................................................................................419 12.1.4 Chapter Outline ......................................................................419
12.2 Basic Properties of Reverberation Chambers......................................... 420 12.2.1 Basic Measurements-Reflection and Transmission
Coefficients ............................................................................ 423. 12.2.2 Transmission Level and Calibration ........................................425 12.2.3. Accuracy and Number of Independent Samples ..................... 426 12.2.4 Research Activities on Reverberation Chambers .....................427 12.2.5 Benchmarking of Reverberation with Anechoic Chambers .... 43.0
12.1 Introduction Multipath fading has for many years been a problem for mobile communication engineers, to be overcome by designing systems that have sufficient signal-to-noise ratio (SNR) or signal-to-interference ratio (SIR) margins. The fading is caused by multiple reflections in walls and ceilings (indoors) or cars and buildings (outdoors) that add constructively or destructively at the location of the terminal or base station antennas. The global system for mobile communications (GSM) and third generation (3.G) both require fading margins of 20-3.0 dB to provide good voice quality at most locations in the cell [1]. The 3.rd Generation Partnership Project (3.GPP) long term evolution (LTE) and, to some extent, evolved HSPA (high-speed packet access) and WiMAX (worldwide interoperability for microwave access) will use a completely different approach to multipath fading. Instead of being something to be combated to provide robust voice communication everywhere in the cell, the fading conditions will be used to increase the bit rate for data communication for single users or increase the system throughput in order to increase the overall spectral efficiency [2].
