Wideband propagation measurements and modeling at millimeter wave frequencies

Millimeter waves offer attractive possibilities for wireless indoor transmission systems and practical application of local area networks for non-voice applications. Advantages over microwaves are the increase bandwidth, smaller antenna and equipment sizes and low probability of interference problem. It should also be adequate for privacy and economy in terms of frequency re-use. Few results are, however, available for wideband channel measurements. Such data are necessary to determine limits on data rates due to channel intersymbol interference. Wideband impulse response phase data have not yet been published and it can be of a great interest for the study of the channel and the design of suitable coding techniques. Results presented in the paper give a clear understanding of the propagation of a 37.2 GHz signal in different environments, making possible the prediction of propagation time delay from the knowledge of the building structure. The number of resolvable multipath components impacts the choice of the form of the channel model. The small number of paths which can be attributed to obvious reflecting objects in the channel encourages the application of a unified numerical procedure to deal with complex bounded electromagnetic field problems. The solution of the 3-D mathematical model based on the time-domain integral equation of the electric field using the boundary element method (TD-BEM) is also introduced