Single-channel heterodyne distance measuring method

Abstract

The present invention relates to a single-channel heterodyne distance measuring method. According to the invention, high precision distance measurement may be carried out by the broadcast of pulsed electromagnetic radiation (ES) with at least two pulse repetition frequencies, whereby the pulse repetition frequencies are selected such that the corresponding pulse separations don not have a common multiple in the range of the order of magnitude of a maximum external measurement range. The radiation is hence transmitted both to a target for measurement over the measurement path outside the device and also over a reference path (6) inside the device, whereby the radiation (IS) passing along the reference path (6) defines at least one start pulse and the radiation (ES) passing along the measurement path defines at least one stop pulse. The radiation (RS) back-scattered from the target and the radiation (IS) passing along the reference path are received and converted into a received signal, from which at least one distance to the at least one target is determined. The radiation (RS) back-scatted from the target and the radiation (Is) passing along the reference path (6) are recorded in parallel, such that the received signal comprises components of the radiation (RS) back-scattered from the target sand the radiation (IS) passing along the reference path.

Description

technical field

[0001] The invention relates to a distance measuring method according to the preamble of claim 1 , a distance measuring device according to the preamble of claim 9 and a computer program product. Background technique

[0002] In the field of electronic distance measurement, various principles and methods are known, and the two basic optoelectronic principles of measurement are embodied as phase meter and transit time meter. Both principles have advantages and disadvantages and are used in a variety of geodetic devices. Therefore, for example, measuring devices such as theodolites or tachymeters used in geodesy are mainly equipped with phase meters because they have the advantages of high precision and compact design, which facilitates integration in telescopes.

[0003] In phase measurement techniques, optical pulses (usually square wave signals) are emitted at repetition rates ranging from a few MHz to hundreds of MHz. In addition to LEDs, conventional CW ...

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