Estimation Method for Actual Quality of Non-Stationary Radio Communication Channels by Telegraph Distortion Value

Radio communication channels for the transmission of discrete messages are typically affected by various types of additive and multiplicative interferences resulting in nonstationary radio lines. The quality of such radio line changes over time and this requires constant adaptation of receiving and transmission apparatus to the conditions of communication. To implement the modes of adaptation, continuous assessment of the quality of communication channels is required. One of the basic criteria for quality assessment of a discrete communication channel is the degree of telegraph (end) distortions for transmitted message unit intervals. This degree is specified by the received power-to-noise ratio. The paper examines the issue of defining the relationship between the signal power-to-noise ratio and the mean value of telegraph distortions for various manipulations (AM, FM, RPM). A relatively simple estimation method is proposed for the current mean telegraph distortion value over the entire period of message reception in a "sliding window" at an assigned limited time interval, this "sliding window" being less than the time interval of communication channel stationarity. The findings of the study can be applied in design of devices for receiver adaptation to communication conditions.