Measurement and analyses of digital TV signals in an indoor environment

An important aspect of terrestrial transmission is indoor portable reception. The quality of service parameters for both indoor and outdoor propagation must be characterized for planning of the number of transmitters and repeaters required to provide minimum acceptable service. Preliminary results of the spatial variation of DVB-T signals received inside an apartment are presented. These are the first experimental results in Singapore and are of interest for future fixed DTV measurements. Measurements made along a line for about 20 wavelengths were analyzed taking different spatial intervals. A running mean technique with different window widths was studied to filter out the fast spatial variations. It is found that, a running mean of one wave length is suitable for averaging. Further, it is observed that the number of samples and spatial intervals are very important in order to arrive at the percentage of coverage. Though the difference observed in the standard deviation is small, it matters very much at higher percentages of probability. A uniform approach must be adopted to allow for a meaningful comparison for measuring and processing the signals for DTV reception.