Abstract
The effects of certain atmospheric conditions upon pulse-code modulation (PCM) data transmission at a carrier frequency of 15.3 GHz are discussed in this paper. Using an amplitude-shift keying (ASK) modulation to transmit 1300000 bit/s across a 9.5 mi line-of-sight path, the performance characteristics of the system, relating to conditions in the channel, were measured and are presented in this study. Theoretical curves of probability of error versus predetection signal-to-noise ratio (SNR), are compared to measured error probabilities; these are obtained at different received signal levels, and under various clear weather conditions ranging from humid to dry. Above 15 dB predetection SNR, the system operates more efficiently than theoretically predicted for ASK modulation over a Rayleigh fading channel. The detected envelope probability distributions are computed for different values of SNR. Results show that drier weather, which causes amplitude fluctuations of a shallow nature, results in greater error probabilities than those for more humid conditions; the term shallow fading is used to describe short term (5-10 min) received signal envelope variations of less than 1 dB. For example, error probabilities for a predetection SNR of 14 dB, ranged from 0.005 to 0.078, from humid to dry conditions respectively. These values fall between the theoretical values of 0.0005 for the nonfading case, and 0.0740 for Rayleigh fading.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.