Abstract:
An optical transceiver includes N transmitters each transmitting one of N transmitted optically bound channels; a clock forwarding mechanism to transmit a transmitted optical clock signal to an opposing optical receiver; N receivers each receiving one of N received optically bound channels; and a clock recovery mechanism to receive a received optical clock signal from the opposing optical transmitter. A method and photonically integrated system are also disclosed. The optical transceiver, method, and system optimize system design of WDM highly parallelized transceivers with optical bound channels, a simplified clocking architecture, and boosted receiver sensitivity. The optical transceiver, method, and system include clock recovery followed by data recovery and can utilize integrate-and-dump optical receivers with a recovered clock.
Abstract:
Système et procédé de transmission optique assurant la transmission d'un trafic de données descendant et montant entre un terminal central (15) et une pluralité de terminaux clients (17) étant connectés entre eux au moyen d'un réseau d'accès optique passif (5), comprenant les étapes suivantes : - une émission de données portées par un signal lumineux (S) multiplexe en amplitude comportant une pluralité d'amplitudes et ayant une longueur d'onde unique vers ladite pluralité de terminaux clients (17) ; - une transformation par décalage spectral, de la longueur d'onde unique dudit signal lumineux (S) envoyé par ledit terminal central (15) en une pluralité de longueurs d'ondes, selon ladite pluralité d'amplitudes formant ainsi un signal lumineux multiplexe par division de longueurs d'onde, de sorte que lesdites données sont reçues par ladite pluralité de terminaux clients (17) selon une pluralité de signaux lumineux (Si,...,SN) ayant une pluralité de longueurs d'ondes différentes, chacun desdits terminaux clients (17) recevant les données qui lui sont associées selon au moins une longueur d'onde spécifique ; et - un routage dudit trafic descendant et montant entre ledit terminal central (15) et les terminaux clients (17).
Abstract:
The invention relates to a method for combined analogue and digital transmission of an analogue AC measuring signal (Sa) by means of an optical fibre, and to a device to carry out this method. According to the invention the analogue AC measuring signal (Sa) is both digitized and combined with a constant direct voltage signal (SR), the digitized AC measuring signal (Sd) and the analog summated signal (SRa) are combined to form a modulation signal and converted to an optical transmission signal (SL), the optical transmission signal is reconverted into a modulation signal in the receiver (6), where the signals (Sa, Sd,SR) are filtered out and the recovered AC measuring signal (Sa) is normalized by the filtered out direct voltage signal (SR). This enables a method for combined analog and digital transmission to be obtained, whereby ageing phenomena of the optical fibre system (2,4,6) can be compensated.
Abstract:
Ein Kopfhörer (1) weist einen Stecker (15) mit einem ersten Anschlusskontakt (16, 17) und einem zweiten Anschlusskontakt (18) sowie einen Lautsprecher (3, 5) auf, der zur Zuführung eines Lautsprechersignals mit dem ersten Anschlusskontakt (16, 17) verbunden ist. Der Kopfhörer (1) weist ferner ein erstes und ein zweites digitales Mikrophon (7, 8, 9) auf, die jeweils eingerichtet sind, ein digitales Mikrophonsignal, insbesondere mit einem binären Bitstrom zu erzeugen. Ein Multiplexer (23), der an einem Ausgang mit dem zweiten Anschlusskontakt (18) gekoppelt ist, ist eingerichtet, auf Basis der Mikrophonsignale ein codiertes Multiplexsignal an dem Ausgang zu erzeugen.
Abstract:
A method and apparatus for synchronizing the secondary side to the primary side of a transformer circuit are presented. A preamble which consists primarily of data pulses and inverted power pulses is used initially to obtain the parameters for and to set up a phase locked loop. For example, an edge-triggered one-shot circuit can be used to generate a reference clock from the preamble until lock is detected. Once the phase lock loop locks onto the clock, normal communication between the primary and secondary commences. The phase lock loop, which is in the secondary, is kept in phase during normal communication using valid Manchester edges from the transmit signal.
Abstract:
The invention relates to a method used for common transmission of digital and analogue modulated radio broadcasting and/or television broadcasting signals, in particular on a broadband cable system. The method provides for at least one digital radio broadcasting and/or television broadcasting signal, in addition to an analogue television broadcasting signal, to be transmitted in at least one channel, the frequency spectrum of at least one digital radio broadcasting and/or television broadcasting signal being restricted to a frequency range which is smaller than the width of the at least one channel. To reduce the analogue television broadcasting signal influence from the at least one digital radio broadcasting and/ or television broadcasting signal, the at least one digital radio broadcasting and/or television broadcasting signal has to be below a predetermined signal level, and the peak level of the analogue television broadcasting signal has to exceed a predetermined value which is substantially higher than the predetermined signal level of the at least one digital radio broadcasting and/or television broadcasting signal. To prevent cross modulation between the analogue and digital modulated radio broadcasting and/or television broadcasting signals, the amplitude of the frequency spectrum of the at least one digital radio broadcasting and/or television broadcasting signal to be below a predetermined value which is substantially smaller than the amplitude of the image carrier of the analogue television broadcasting signal.
Abstract:
The arrangement serves to transmit signals in a measurement circuit which comprises a measurement transmitter (10) and an evaluation unit (20) located at a distance therefrom. The measurement transmitter is connected to the evaluation unit by a twin-conductor lead (15), via which on the one hand the measurement value signals are transmitted from the measurement transmitter to the evaluation unit and via which on the other hand the d.c. supply current required for operation of the measurement transmitter is transmitted from the evaluation unit to the measurement transmitter. In oder to form the measurement signals the measurement transmitter converts the measurement value to be transmitted into constant-amplitude pulse-modulated measurement-value current pulses, which are superimposed on the d.c. supply current in the twin-conductor lead. To effect the connection with the twin-conductor lead the evaluation unit has an evaluation interface (23) which contains a signal receiver responding to the measurement value current pulses. In addition, at least one communication unit (30) is provided which, when required, can be connected to the twin-conductor lead. To effect connection with the twin-conductor lead the communication unit contains a communication interface (33) designed for emitting communication signals. The communication interface contains a signal generator which produces pulse-modulated communication current pulses, the pulse amplitude of which is different from the pulse amplitude of the measurement value current pulses, and which are superimposed on the d.c. supply current in the twin-conductor lead in the form of communication signals. The signal receiver of the evaluation interface contains an amplitude discriminator to distinguish the measurement value current pulses from the communication current pulses on the basis of their different pulse amplitudes. The signal generator of the evaluation interface switches the d.c. supply voltage to the twin-conductor lead according to the pulse modulation of the communication signal between the two voltage values, and the signal receiver of the communication interface responds to the pulse-modulated voltage changes. As a result the communication unit and the evaluation unit can exchange information over the twin-conductor lead without the transmission of the measurement value signals over the same twin-conductor lead being impaired.
Abstract:
Embodiments herein relate to a method performed by a network node (110) for performing a superposed transmission in a wireless communications network (100), wherein the superposed transmission comprises a first signal intended for a first wireless device (121) from the network node (110) and a second signal intended for a second wireless device (122) from the network node (110) that are superposed and transmitted simultaneously by the network node (110) on the same transmission resources in the wireless communications network (100). The network node (110) determines a first ratio of the total transmission power (P) available for the superposed transmission, which first ratio is to be used for the first signal in the superposed transmission. Also, the network node (110) determines a second ratio of the total transmission power (P) available for the superposed transmission, which second ratio is to be used for the second signal in the superposed transmission. Then, the network node (110) transmits information indicating the first and/or second ratio to at least the first wireless device (121) in the wireless communications network (100). Thereafter, the network node (110) performs the superposed transmission to the first and second wireless device (121, 122) simultaneously on the same transmission resources by transmitting the first signal using a transmission power according to the first ratio and by transmitting the second signal using a transmission power according to the second ratio. Embodiments of the network node (110) are also described. Embodiments herein also relate to a first wireless device (121) for handling a superposed transmission from a network node (110) in a wireless communications network (100) and a method therein. Embodiments herein also relate to a second wireless device (122) for handling a superposed transmission from a network node (110) in a wireless communications network (100) and a method therein.