Abstract: A mobile object configured for movement in an area equipped with VLC illumination sources comprises a light sensor arranged to detect illumination from at least one of the illumination sources within the view of the light sensor; a computer arranged to determine from the detected illumination (i) a position of the mobile object relative to the at least one illumination source and (ii) the identifier of the at least one illumination source; and a transceiver. The transceiver can receive from another mobile object a message comprising the position of the other mobile object relative to a source of illumination, and the identifier of that source of illumination. From this, the computer determines from its position and the message a distance from the other mobile object. A mobile object which transmits such a message is also envisaged.

Abstract: A lighting system comprises multiple luminaries (4b) installed at known locations in an environment. Each is configured to emit a unique luminaire identifier (ID) into the environment. A database (28) holds multiple location identifiers, each of which identifies one of the known locations. A route (rA, rB, rC, rD) through the environment is identified based on the location identifiers, the route traversing a plurality of the known locations. Data generated by moving a photodetector (6) along the route though the environment is received, the data conveying a sequence of the luminaire identifiers detected by the photodetector from luminaries encountered in moving along the route, the sequence being in order of detection. A database update is performed by, for at least one luminaire identifier in the sequence: identifying its position in the sequence, and updating the database based on the at least one luminaire identifier and its identified position in the sequence.

Abstract: A lighting system comprises multiple luminaries (4b) installed at known locations in an environment. Each is configured to emit a unique luminaire identifier (ID) into the environment. A database (28) holds multiple location identifiers, each of which identifies one of the known locations. A route (rA, rB, rC, rD) through the environment is identified based on the location identifiers, the route traversing a plurality of the known locations. Data generated by moving a photodetector (6) along the route though the environment is received, the data conveying a sequence of the luminaire identifiers detected by the photodetector from luminaries encountered in moving along the route, the sequence being in order of detection. A database update is performed by, for at least one luminaire identifier in the sequence: identifying its position in the sequence, and updating the database based on the at least one luminaire identifier and its identified position in the sequence.

Abstract: This invention discloses an alternative communication and control path that can by-pass a primary communication and control line in the control luminaires of an illumination network luminaires. By creating the alternative back-up path, it is possible to still communicate and control network elements in cases when the primary communication and control path is unavailable or when direct control of individual or a plurality of luminaries is desired. In one aspect of the invention, this alternative path may provide for a direct interface for demand response utility programs for specialized control of the luminaires of the illumination network.

Abstract: This invention discloses an alternative communication and control path that can by-pass a primary communication and control line in the control luminaires of an illumination network luminaires. By creating the alternative back-up path, it is possible to still communicate and control network elements in cases when the primary communication and control path is unavailable or when direct control of individual or a plurality of luminaries is desired. In one aspect of the invention, this alternative path may provide for a direct interface for demand response utility programs for specialized control of the luminaires of the illumination network.

Abstract: The invention relates to embedding data symbols of a data signal into a luminance output of an illumination device. The device includes a controller configured for receiving a first base pattern and a second base pattern within a frame period, and generating a shifted second pattern by phase shifting the second base pattern within the frame period with respect to the first base pattern in response to the data signal such that the data symbols are embedded in the luminance output of the device. The device also includes a first light source configured to generate a first luminance output in response to the first base pattern and a second light source configured to generate a second luminance output in response to the shifted second pattern. The first and second luminance outputs have different output spectra and the luminance output of the illumination device comprises both the first and second luminance outputs.

Abstract: A lighting device (10) comprises a LED (4), a driver (3), and a controller (2) which regularly switches from a drive state to a measuring state and back. In the measuring state, the controller controls the driver such that the driver does not generate any LED current. The LED produces a measuring signal (Sm) indicating a measured light level. The controller processes the measuring signal received from the LED, and makes a decision on the desired light output of the LED. In the drive state, the controller controls the driver such that the average light output produced by the LED corresponds to the desired light output as determined in the measuring state. In a possible embodiment, the driver generates a nominal LED current INOM, and sets the duration (?1) of the drive state on the basis of the desired light output of the LED as determined in the measuring state.

Abstract: The invention relates to embedding data symbols of a data signal into a luminance output of an illumination device. The device includes a controller configured for receiving a first base pattern and a second base pattern within a frame period, and generating a shifted second pattern by phase shifting the second base pattern within the frame period with respect to the first base pattern in response to the data signal such that the data symbols are embedded in the luminance output of the device. The device also includes a first light source configured to generate a first luminance output in response to the first base pattern and a second light source configured to generate a second luminance output in response to the shifted second pattern. The first and second luminance outputs have different output spectra and the luminance output of the illumination device comprises both the first and second luminance outputs.

Abstract: A lighting device (10) comprises a LED (4), a driver (3), and a controller (2) which regularly switches from a drive state to a measuring state and back. In the measuring state, the controller controls the driver such that the driver does not generate any LED current. The LED produces a measuring signal (Sm) indicating a measured light level. The controller processes the measuring signal received from the LED, and makes a decision on the desired light output of the LED. In the drive state, the controller controls the driver such that the average light output produced by the LED corresponds to the desired light output as determined in the measuring state. In a possible embodiment, the driver generates a nominal LED current INOM, and sets the duration (? 1) of the drive state on the basis of the desired light output of the LED as determined in the measuring state.