Abstract:
A system for providing underwater communication using orbital angular momentum (OAM) includes a transmitter that processes input data to be transmitted using pre-coding information based on current transmission channel conditions to maximize data rate based on channel conditions. A receiver receives a transmitted multiplexed OAM optical signal and analyzes the received signal for channel state information. The channel state information is used to determine a set of pre-coding values that allow the transmitter to pre-code the input data to maximize the data rate based on current channel conditions. The pre-coding values are mapped to a codebook entry which identifies the pre-coding values. The codebook entry is transmitted from the receiver to the transmitter. The transmitter uses the received codebook entry to identify pre-coding values used to process subsequent input data to be transmitted in order to enhance data rate across the transmit channel.
Abstract:
An optical network is provided comprising a first node (503) and a channel drop add device (501). The first node (503) is configured to transmit data onto an optical fiber in a first line direction. The channel drop add device (501) is adapted to receive and add channels onto the optical fiber (502) thereby transmitting the data into the first and a second line direction (502a, 502b). The network further comprises a second node (507) configured to form a transmitter/receiver function. The second node is configured to receive data on said optical fiber from said first and second line directions, wherein the second node is adapted to convey data to a client interface for the data received for either said first or second line direction. The second node (507) is further configurable to transmit data into the first and second directions towards the channel add drop device using two line interfaces. The second node (507) is configured to convey data from the client interface into one direction, the active line direction, selected from said first and second directions (502a, 502b) and the second node is configured to not convey data from the client interface into the other line direction, standby line direction, selected from said first and second directions. Further, the second node (507) is adapted to synchronize received data from said first and second line directions by delaying (D) the data signals seeing the shortest delay, by a delay device.
Abstract:
A bidirectional optical fiber path includes a primary optical fiber path; a secondary optical fiber path coupled to the primary optical fiber path; an optical coupler coupled to both the primary optical fiber path and the secondary optical fiber path; an optical switch coupled to both the primary optical fiber path and the secondary optical fiber path, the optical switch selecting a path of lower optical loses; an optical cross-bar switch coupled to both the primary optical fiber path and the secondary optical fiber path and located between the optical coupler and the optical switch; a primary upstream light detector coupled to the primary optical path between the optical cross bar switch and the optical switch; a secondary upstream light detector coupled to the secondary optical path between the optical cross bar switch and the optical switch; a primary downstream light detector coupled to the primary optical path between the optical cross bar switch and the optical switch; a secondary downstream light detector coupled to the secondary optical path between the optical cross bar switch and the optical switch; and a stabilizing downstream light detector coupled to the primary optical fiber path between the optical coupler and the optical cross bar switch.
Abstract:
본 발명에 따른 광선로 검사기는, 적어도 광선로의 절단 위치를 측정하기 위한 광선로 검사기로서, 복수의 파장이 번갈아 가면서 주기적으로 나타나는 제 1 광신호를 생성하는 제 1 파장가변 레이저 소스(TOS1); 상기 제 1 광신호와 동일하면서 조절되는 지연시간을 가진 제 2 광신호를 생성하는 제 2 파장가변 레이저 소스(TOS2); 상기 광선로로 출사된 제 1 광신호가 되돌아온 반사 광신호와, 상기 제 2 광신호의 사이에 간섭을 일으켜서 간섭 신호를 출력하는 간섭계(IFM);를 포함하는 것을 특징으로 한다.
Abstract:
An apparatus for inline monitoring of transmit signals is disclosed. The apparatus includes a processor, and one or more fiber optic lines for supplying a transmit signal to/from a remote transmission station. The processor is configured to receive input for selecting one or more fiber optic lines for examination, determine at least one property of the transmit signal to be monitored, and retrieve information corresponding to the at least one property for a predetermined period of time. The processor is further configured to output a visual representation of the retrieved information, perform an analysis of the retrieved information and the visual representation, and facilitate identification of at least one status associated with the transmit signal based, at least in part, on the analysis.
Abstract:
A distributed acoustic sensing system and a method of obtaining acoustic levels using the distributed acoustic sensing system are described. The distributed acoustic sensing system includes an optical fiber, a light source to inject light into the optical fiber, and a photodetector to sample a DAS signal in each section of one or more sections of the optical fiber resulting from two or more points within the section on the optical fiber over a period of time. The system also includes a processor to process only a low frequency portion of the DAS signal to obtain the acoustic levels at each of the one or more sections on the optical fiber over the period of time, the low frequency portion of the DAS signal being less than 10 Hz.
Abstract:
A pluggable active optical module (AOM) having an electrical connector at a first end and one or more optical adapters at a second end is disclosed. The AOM includes a storage device interface at the second end, and a programmable processor coupled to the storage device interface and one or more first contacts of the electrical connector. The programmable processor is configured to access a storage device in one or more optical fibers through the storage device interface and provide physical layer management (PLM) information obtained therefrom to a host device connected to the electrical connector. The AOM also includes a switch coupled between a second contact of the electrical connector and ground, the switch coupled to the programmable processor such that programmable processor can control the switch to selectively connect a second contact of the electrical connector to ground.
Abstract:
There is provided a method of processing for alarm clearing for alarm occurred in an apparatus, the method including the steps of: (a) sending a hardware interrupt request for an alarm occurring to a processor; (b) determining a parameter for the alarm; (c) obtaining a current value for the parameter by periodic software polling; (d) obtaining a threshold value for the parameter; (e) determining whether the current value is within the threshold value; and (f) processing for alarm clearing of the alarm if the current value is within the threshold value.