摘要:
A two-dimensional wavelength/time optical CDMA system employing balanced-modified pseudo random noise (PN) matrix codes is provided. Through an inverse-exclusive OR operation of a pair of modified PN code, the balanced codes are generated as optical CDMA codes in the form of a new matrix. When the codes are applied to an optical CDMA system to perform encoding and decoding, if the same number of channels as the number (M−1) of subgroups of the codes are connected, the system becomes an MAI-free system, and even if the number of channels connected is twice the number of the subgroups, an error-free system can be established. Accordingly, the number of channels that can be used simultaneously is doubled compared to the prior art method such that the economical efficiency of the optical CDMA system improves.
摘要:
Disclosed herein are a CDMA optical system and encoder and decoder included therein. Time domain encoding means creates a time domain code having a sequence according to inputted data bits or a complementary code which is complementary to the time domain code. An optical modulation means selectively outputs lights, in which the lights are incident upon the optical modulation means from the outside, to two output leads, respectively, according to chip bits of the time domain code or the complementary code. A wavelength domain encoding means encodes the light outputted from a first output lead of the optical modulation means to a wavelength domain sequence (two dimensional code), transmits the wavelength code to the base station, encodes the light outputted from a second output lead to a complementary sequence of the wavelength domain sequence, and transmits the complementary code of the two dimensional code to the base station.
摘要:
Provided are an acousto-optic filter and an optical code division multiple access (CDMA) system using the acousto-optic filter. The acousto-optic filter includes: an acousto-optic mode converter (AOMC) converting an optical signal of a specific optical frequency corresponding to a frequency of an electric signal of an optical signal of a first mode having a predetermined optical frequency band; and a mode stripper (MS) stripping an optical signal of the optical signal of the first mode that has been converted to a second mode.
摘要:
An optical power distributor is coupled to a high-intensity broadband light source to distribute in a shared manner an output of the high-intensity broadband light source to a plurality of optical line terminals. A depolarizer is also described having an input coupled to an output of a polarized broadband light source. A first integrated module has optical transmitters and an optical wavelength router for a first band. A second integrated module has optical receivers and an optical wavelength router for a second band.
摘要:
A method of allocating radio resources in a multi-carrier system is disclosed, by which a signaling message can be efficiently transmitted according to necessity of a user equipment. In a user equipment of a mobile communication system transceiving data using a plurality of subcarriers, the present invention includes the steps of if the signaling message to be transmitted is generated in the user equipment, generating a preamble sequence according to a user equipment identifier to identify the user equipment, transmitting a preamble signal including the preamble sequence and the signaling message to a base station, and receiving an acknowledgement signal for the preamble signal generated according to the user equipment identifier.
摘要:
A method for implementing a redundant structure of an ATCA system via a base interface of a network system based on an ATCA standard, and the ATCA system for use in the same are disclosed. Each of routing protocol shelves and LI shelves includes two ports connected to two IPC paths provided from the base interface, such that a representative IP address is assigned to a single port to be used, performs IPC communication using the representative IP address. If a port error or link-down state occurs, the representative IP address is assigned to the other port, resulting in the implementation of stable IPC communication. If the port error or link-down state occurs in an active-mode ShMC shelf, an IPC path passing through a standby-mode ShMC shelf is provided.
摘要:
A thin film transistor array substrate comprises thin film transistors and pixel electrodes formed at respective pixels that are defined by gate lines and data lines that orthogonally intersect each other. The thin film transistor array substrate further comprises a plurality of gate pad units that group a plurality of gate pads extended from the gate lines, and a plurality of data pad units that groups a plurality of data pads extended from the data lines. The thin film transistor array substrate further includes a plurality of gate test terminals connected to the gate pad units and beside at least one side of the respective gate pad units, and a plurality of data test terminals connected to the data pad units and located beside at least one side of the respective data pad units.
摘要:
An LCD test method and apparatus for reducing the number of channels of a probe unit is provided. An apparatus for testing a liquid crystal display including: a stage on which a liquid crystal panel is placed; a plurality of vertically divided blocks, wherein each of the vertically divided blocks include a plurality of adjacent data lines; a data probe unit that provides test pattern signals respectively to groups of at least two of the plurality of vertically divided blocks of the liquid crystal panel; a plurality of horizontally divided blocks, wherein each of the horizontally divided blocks include a plurality of adjacent gate lines; a gate probe unit that provides scanning signals respectively to the plurality of horizontally divided blocks of the liquid crystal panel; and a controller that provides test pattern signals to the data probe unit and provides scanning signals to the gate probe unit.
摘要:
The present invention relates to a probe card that a probe of the probe card is movable only in a vertical direction using a trench to improve a electrical or a mechanical characteristic and to automatically limit the vertical movement thereof within a predetermined range. A pitch may be reduced so as to correspond to a decreasing distance between pads. A flatness of a probe tip may be maintained within a few micrometers using a semiconductor manufacturing process. 32 simultaneous parallel testing is possible contrary to a convention probe card. A wafer level testing is possible, and time and cost for a wafer testing are reduced.
摘要:
An emergency alert message is included in a cable broadcast signal. The emergency alert message includes major and minor details channel numbers associated with a details channel. A details channel number is configured based on the major details channel number when the minor details channel number is set to a null value. Next, it is tuned to a channel frequency of a digital cable channel corresponding to the details channel number when the details channel number exists in a digital channel number list. Alternatively, the emergency alert message includes a details channel source field which indicates whether a details channel is a digital or an analog channel. Then, it is tuned to a channel frequency of one of a digital cable channel and an analog cable channel based upon a value of the details channel source field.