Bounds on communication

Six parameters of importance in many communication systems are: (a) the rate at which digital information is transmitted; (b) the bandwidth of the system; (c) the signal power of the transmitted signals; (d) the noise power of disturbances in transmission; (e) the error probability in digits recovered at the receiver output; (f) the length of time that the transmitter and receiver can store their inputs. These six parameters cannot assume arbitrary values: certain sets of values cannot be realized. In a series of curves, this paper describes the boundary between compatible and incompatible sets of parameter values. In the model studied, it is assumed that the disturbance is additive Gaussian noise with constant power density spectrum in the transmission band.