This paper presents a prediction of the millimeter-wave multipath propagation characteristics in the typical urban environment. To analyze the propagation in an outdoor environment, the three dimensional model based on the geometrical optics and the uniform geometrical theory of diffraction is employed. Prediction by the three dimensional ray tracing method needs a detailed map, which records locations and shapes of obstacles surrounding a transmitter and a receiver. It is usually difficult to create a complete map because tremendous data is necessary to describe the area structure. We propose, in this report, a three dimensional propagation model to predict the millimeter wave propagation characteristics by using the information available from only a map on the market. This approach gives us much convenience in the actual design. The modeled results are demonstrated and furthermore comparison are made between the simulated results and the experimental data.

It is expected that software receivers will be widely available for radio communication, broadcasting and radio monitoring applications because they are able to be equipped with multimode, multirate and multiband functions in a single hardware platform. This paper describes the basic techniques required for software receivers for both hardware and software. The evaluation items and methods were studied and some evaluations done with an experimental software receiver model fabricated for radio monitoring applications. Future concepts in radio communication, broadcasting and radio monitoring applications where software receivers are thought to be suitable, were studied, and problems for realization identified.

Differential detection of π/2-TFSK, which turns to MSK and π/2 shift PSK in the limitting cases, is analyzed in order to find conditions under which the error performance is not degraded severly and to make clear the relationship between error characteristics of MSK and PSK differential detection in the multipath interfering channel. A two-wave model of two Rayleigh waves is adopted as a frequency selective channel. The conditions under which the π/2-TFSK scheme is able to be implemented and detected with the differential detection are investigated. It is indicated that these can be realized by CPFSK. It is shown that existence of a flat part in the excess phase transition exhibits an important role in order not to be severly corrupted by the multipath interference.

Millimeter-wave propagation characteristics are measured in the outdoor environments. Especially, specific features in the urban area and the open meadowland are compared.