A high-reliability digital angle encoder

Аuthors

Alekseeva V. V.

JSC «SRTI «Avangard», Saint Petersburg, Russia

e-mail: ladarobotics@gmail.com

Abstract

This paper presents an analytical model of a high-information-reliability digital angle encoder with correction of multiple errors based on the theory of M‑sequences and Bose–Chaudhuri–Hocquenghem (BCH) cyclic codes. The proposed method solves a key problem in precision measurement technology (aviation and space) — achieving high noise immunity while maintaining minimal size, weight, and structural complexity. In contrast to code scales that require dedicated tracks for redundant or parity sensors, the use of a pseudorandom code scale enables error-correction capability to be embedded directly into the existing scale structure. The core of the approach lies in constructing a generator polynomial of a cyclic code over an extended Galois field, which provides an optimal trade-off between redundancy and error-correcting capacity. This work is a development of Hamming coding methods that provide single-error correction and extend them to correct an arbitrary number of errors with a minimum code distance. The simulation results confirm the model's performance for 5...16-bit data, which corresponds to M-sequence periods of 31...65535 characters.

Keywords:

error correction; pseudorandom code scale; digital angle encoder; BCH codes; Galois field; cyclic codes; Berlekamp — Massey algorithm

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