Limits RegistryPUBLIC RECORDLimits RegistryResearch Console →Maximum zero-inter-symbol-interference symbol rate of an ideal real baseband channel of bandwidth B.
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Upper-bound symbol rate for ideal pulse transmission over a noiseless real baseband channel with one-sided bandwidth B and zero ISI.
The most obvious method for determining the distortion of telegraph signals is to calculate the transients of the telegraph system. This method has been treated by various writers, and solutions are available for telegraph lines with simple terminal conditions. It is well known that the extension of the same methods to more complicated terminal conditions, which represent the usual terminal apparatus, leads to great difficulties. The present paper attacks the same problem from the alternative standpoint of the steady-state characteristics of the system. This method has the advantage over the method of transients that the complication of the circuit which results from the use of terminal apparatus does not complicate the calculations materially. This method of treatment necessitates expressing the criteria of distortionless transmission in terms of the steady-state characteristics. Accordingly, a considerable portion of the paper describes and illustrates a method for making this translation. A discussion is given of the minimum frequency range required for transmission at a given speed of signaling. In the case of carrier telegraphy, this discussion includes a comparison of single-sideband and double-sideband transmission. A number of incidental topics is also discussed.
Certain topics in telegraph transmission theory — Nyquist zero-ISI symbol-rate boundCurrent frontiers derived from accepted Claims.
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Only accepted Claims matching the current specification contribute to the displayed bounds. Strict inequalities remain open; contradictory Claims require editorial review.
Limits Registry. LR-003401. Nyquist zero-ISI symbol-rate bound. 2026.