Transmission characteristics of wireless baseband transmission under multipath environments using real-valued signal analysis.

Discussed here are real-valued signal analysis and wireless baseband transmission, a system for transmitting baseband signals directly from an antenna, and transmission characteristics under a multipath environment. The field of wireless transmission generally handles band signals in which information rides on a carrier wave, and therefore signal analysis is not the direct analysis of real high-frequency signals (real-valued signals) and is performed with a system expressed using complex numbers, called an equivalent baseband system. However, wireless baseband transmission is based on a transmission system which does not use carrier waves and cannot be handled with an equivalent baseband system. Consequently, it is necessary to have a system of real-valued signal analysis for handling baseband signals, which are real-valued signals, without additional processing. The BER (bit error rate) was used as the standard for evaluating transmission characteristics under a multipath environment of wireless baseband transmission using measured channel characteristics with that algorithm. With a computer, the BER characteristics were found by varying the reflection coefficient, number of delay symbols, the ratio of direct wave power and reflected wave power, and the number of reflected waves. As a result, it was clear that the dominant factor in a multipath environment is the ratio of direct wave power and reflected wave power. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(10): 9–22, 2007; Published online in Wiley InterScience (<URL>www.interscience.wiley.com</URL>). DOI 10.1002/ecjb.20347 [ABSTRACT FROM AUTHOR]