† Supported in parts by the Alberta Informatics Circle of Research Excellence (iCORE), the Natural Sciences and Engineering Research Council (NSERC) of Canada, the Canadian Foundation for Innovation (CFI) and the National Sciences Foundation (NSF) under grant ECS 9979323. Abstract A mobile 4x4 multiple input multiple output (MIMO) system has been constructed and used to perform wireless measurement campaigns on non-line of sight (NLOS) channels in an indoor office setting. The MIMO system uses orthogonal 500 kchips/s Walsh coded signals that are filtered and simultaneously transmitted at 916 MHz. Two identical campaigns were conducted: one with antenna spacing of λ/4 at both the transmitter and receiver stations and another with antenna spacing of λ/2. The complex MIMO channel matrices obtained in the campaigns were used to calculate the theoretical capacity for a 4x4 system. Our measurements show a slightly higher average channel capacity for the λ/2 case as compared to the λ/4 case (20.2 bits/use vs. 18.6 bits/use).The 90 percentile channel capacity is 18.0 bits/use for the λ/2 spacing and 16.5 bits/use for the λ/4 spacing.
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