Signal to noise ratio measurements of directional versus omnidirectional antennas at 1990 MHz

We evaluate the SNR of a 1.25 MHz channel in three antenna receive configurations at 1990 MHz. In particular, we evaluate the SNR both inside and outside an apartment using two omnidirectional antennas and one directional antenna. Other results we derive include wall penetration or propagation loss into the residence as well as the noise rise. We test two multi-dwelling units (MDUs) in different orientations to the transmitter and compare results. In general the results suggest that a directional antenna placed outside the apartment typically has a higher SNR than the omnidirectional antenna placed inside the residence. Furthermore, the SNR of all three antennas tested outside the apartment was higher that the SNR measured indoors. Contributing factors to the degradation of SNR indoors are both penetration loss into the residence as well noise rise experienced when placing the antenna indoors. The results in the paper are from field experiments conducted at US WEST Advanced Technologies in Boulder, Colorado. Theoretical treatments to the expected antenna noise temperature are also discussed.