Distance-measuring method and transmitting and receiving station for carrying out the same
AssigneeAlcatel
InventorsAlessandro Bianchi, Guiseppe Comito, Andrea Fantini
Life of this patent
Estimating the term…
Abstract
In an optical communication system with a passive star coupler, measurement between a station and a central node should not interfere with the operation of other stations. Distance measurement is accomplished by determining the echo delay using a wavelength not being used by other stations. The system uses combined wavelength- and time-division multiplexing. One wavelength is always kept free for measurements if possible. For the measurement, the same data format as that employed during normal operation can be used. Measurement can be continuously repeated unchanged during operation.
Claims19
Method of measuring the distance from a station of a passive optical star network to a central node of said passive optical star network when said station is put into operation, comprising the steps of:
- transmitting a signal on a wavelength not being used for message transmission;
- and
- measuring delay until receipt of an echo signal, whereby the delay corresponds to a distance measurement.
An apparatus for measuring the distance from a station of a passive optical star network to a central node of said passive optical star network when said station is put into operation, comprising:
- means for transmitting on a wavelength not being used for message transmission;
- and
- means for measuring delay until receipt of an echo signal, whereby the delay corresponds to a distance measurement.
Transmitting and receiving station for a passive optical star network, comprising:
- an optical transmitter for transmitting messages in a first wavelength;
- and
- an optical receiver for receiving messages in said first wavelength,
- wherein the transmitter and the receiver are switchable to a second wavelength range, the station includes a comparing device which supplies a comparison between data received by the receiver and data previously transmitted by the transmitter, and the station includes a measuring device for measuring delay from the transmission of data to the reception of data matching the transmitted data.
Dependencies are inferred from the claim text.