Abstract:
An uplink subsystem for use in an illumination system arranged for optical communication as well as the illumination system, the system comprising a downlink subsystem and the uplink subsystem. The uplink subsystem comprises sensors (e.g. infrared sensor) embedded in each luminaire in the group. The uplink subsystem also comprises a demodulator, and a distribution network for supplying the signals sensed to an adaptor to combine instances of the sensed uplink signal in a manner that takes into account a Time Division Medium Access scheme and a demodulator to demodulated the combined signal. The system further comprising a downlink subsystem that in turn comprises a modulator for generating a modulated waveform, and an optical fiber distribution network to distribute the modulated waveform to each luminaire in a group. Each such luminaire generates a drive current for driving a lighting element of that luminaire to emit light. Each also injects the modulated waveform into its drive current so as to embed the downlink signal in the emitted light.
Abstract:
The disclosure relates to an apparatus comprising a pole such as a light pole (1), and one or more removable modules (4) adapted to be removably fitted to the pole. The apparatus further comprises, included in the lighting module or another of the modules, a controller (14) comprising a wireless receiver (17) for wirelessly receiving on-off signals from a remote control system (19). An inductive coupling (22) between a primary winding (22i) in the light pole and a secondary winding (22ii) in the lighting module is used to transfer power from a power supply of the pole to at least one of the removable modules, in order to power an element of that module. Further, a magnetic coupling is used to enable the controller to control a switch (9) in the pole in order to connect and disconnect the primary winding to and from the power supply (6,7).
Abstract:
An LED module (200) comprising: a first set of LEDs (D1) for emitting illumination to illuminate an environment, arranged within a first circuit path; a second set of one or more LEDs (D2) for emitting light, arranged within a second circuit path; both the first and second sets being powered by a portion of the power received via a same pair of input terminals, and the first circuit path being longer than the second circuit path; and filter circuitry (206, 208) arranged to filter a modulation in the power received via the terminals, the filtering comprising allowing a component of the modulation at a predetermined modulation frequency to be passed only to the second set of LEDs (D2) and not the first set (D1), thereby causing a corresponding signal to be embedded in the light emitted by the second set but not in the illumination emitted by the first set.
Abstract:
A lighting circuit and a method of operating a lighting circuit are described. A rectifier (14) has an input for an alternating voltage V. At least a first and a second LED assembly (20, 22) are connected to be supplied with electrical power from the rectifier (14). The first LED assembly (20) is electrically connected to a first output (26) of the rectifier (14) and electrically connected in series with an input (36) of a switching converter circuit. The second LED assembly (22) is electrically connected to an output (48) of the switching converter circuit (44). A control assembly (30) is connected to a tap (46) in the series connection for controlling operation of the first LED assembly (20).
Abstract:
Apparatuses (100) for driving loads (200) receive input signals in first, normal situations and provide first output signals to series arrangements of the loads (200) and rechargeable sources (300) to feed the loads (200) and charge the sources (300) with input power provided via the input signals. In second, emergency situations, converters (11-13) convert source signals from the sources (300) into second output signals destined for the loads (200) to feed the loads (200) with source power provided by the sources (300). The converters (11-13) may comprise converter-switches (11) and inductors (12) and diodes (13), and, in first modes of the converter-switches (11), couple the inductors (12) and the sources (300) for charging the inductors (12) via the source signals. In second modes of the converter-switches (11), the inductors (12), after being charged, provide the second output signals. The converters (11-13) may further regulate values of the first output signals. Load- switches (21) may de-activate the loads (200) and source-switches (31) may bypass the sources (300).
Abstract:
A retrofit Light Emitting Diode, LED, tube for replacing a fluorescent tube, wherein said retrofit LED tube is arranged to be connected to a ballast, said retrofit LED tube comprising a ballast determining unit arranged for identifying a type of ballast connected to said retrofit LED tube by controlling an output voltage of said power rectifier to a first voltage and measuring a first current provided by said power rectifier, controlling said output voltage of said power rectifier to a second voltage and measuring a second current provided by said power rectifier, wherein said second voltage differs from said first voltage and determining said type of ballast based on said first and second output voltages and said measured first and second currents, wherein said ballast determining unit is further arranged to configure said configurable matching circuit based on said determined type of ballast.
Abstract:
The invention provides a current modulating circuit, for example for use in a driving circuit for driving a lighting load such as an LED arrangement. A current modulating element is provided in series with the lighting load, and modulates the current based on a data input signal. A feedback system controls the current modulating element, and it has a first feedback control path which uses a voltage across the current modulating element, and a second feedback control path which uses the data input signal. The voltage feedback is used to maintain the overall current equal to the current output from a driver. The difference in current is taken up by a capacitor at the output of the driver.