摘要:
In a direct sequence spread spectrum communications system wherein user binary information symbols are spread spectrum modulated and transmitted to the other party, a non-coherent Walsh QPSK and a coherent Walsh QPSK modulation methods, wherein the PN spreading sequences for inphase and quadrature data in a conventional QPSK PN modulation scheme are coded by Walsh sequences indexed by a special rule to reduce the envelope variation of the transmitted signal, can reduce the envelope variation of transmit signal. And, in a direct sequence spread spectrum communications system wherein several user binary information symbols are spread spectrum modulated, the information symbols of each user are covered by user-specified different Walsh codes and transmitted to the other party, a QPSK modulation methods, wherein the polarity of quadrature PN spreading sequence of a user is controlled by a system controller to make the number of users using the quadrature PN sequence equal to that of users using NOT of the sequence, can reduce the envelope variation of transmit signal.
摘要:
A channel structure for performing a coherent demodulation in reverse links respectively adapted to transmit pilots from a plurality of mobile stations to a base station in a wideband code division multiple access (CDMA) mobile communication system, wherein burst pilots are respectively transmitted from the mobile stations within predetermined time slots so that they can be staggered with reference to the start point of every superframe. Since a pilot burst adjustment is carried out in accordance with the present invention, it is possible to obtain an increased channel capacity as compared to that of the reverse link according to the IS-95 standard scheme. The receiver of the base station can also have a simple and inexpensive structure.
摘要:
Speech path switching control apparatus and a method for making maintenance of speech possible even upon occurrence of a fault in echo cancellation. The speech path switching control apparatus includes a time switch for receiving PCM voice data from a space switch through a switch network link and performing time slot interchange with trunk lines, an echo canceller connected to the time switch through a plurality of sub-highways to cancel echoes, an access switching processor for discriminating whether echo cancellation is required for a trunk call allocated with a particular one of the trunk lines and outputting the resultant discrimination signal, and a time switch control processor for controlling the time switch and the echo canceller in response to the discrimination signal from the access switching processor. If the echo cancellation is not required or the echo canceller is abnormal, there is formed a speech path which is not passed through the echo canceller. In the case where the echo cancellation is required and the echo canceller is normal, there is formed a speech path which is passed through the echo canceller.
摘要:
A method of connecting to an online service where a terminal transmits information regarding a selected online service and first authentication information to an external device, receives second authentication information detected based on the transmitted information, from the external device, and is then logged into the selected online service based on the received second authentication information.
摘要:
An apparatus having a coherent light source, an optical sensor, and a controller that can be utilized in optical mice and the like is disclosed. The coherent light source emits coherent light in a cone of angles about an illumination direction. The optical sensor includes an array of photodetectors disposed on a die having a surface substantially perpendicular to the illumination direction. The controller compares first and second images recorded by the optical sensor at different times and determines a displacement indicative of the direction and distance the apparatus has moved between the two different times. A portion of the coherent light source is bonded to the die at a location within the array of photodetectors.
摘要:
Magnetic force is used to re-center a puck in a pointing device or similar transducer-based device. A user can apply finger pressure to move the puck laterally away from the central position. The puck has a first magnet system, and the base of the device has a second magnet system. The magnetic repulsion or other magnetic interaction returns the puck to a central position when the user removes the finger pressure.
摘要:
A method for automatically switching an incoming call signal output mode in a mobile communication terminal is disclosed. The method comprises the steps of determining whether or not a present incoming call signal output mode is a vibration mode when receiving incoming call, driving a vibrator to output vibration if it is determined that the present incoming call signal output mode is set to the vibration mode, detecting an intensity of actual vibration of the terminal via a vibration detection sensor when the vibration is output, followed by calculating transfer energy using the intensity of the actual vibration on the terminal, and automatically switching the incoming call signal output mode from the vibration mode to a ringtone mode according to comparison of the calculated transfer energy with a reference value. With the method, a user can easily recognize the incoming call signal.
摘要:
Inside frame of a compressor including a frame body having a pass through hole for a crankshaft, legs formed by bending, and extending from, opposite ends of the frame body, respectively, and component fastening parts formed by extending from the legs in parallel to the frame body, respectively, wherein the component fastening parts have opposite inward extensions, and the frame body is formed such that component fastening to the component fastening parts is possible without interference with the frame body, thereby minimizing a size of the compressor and enhancing an assembly precision and strength.
摘要:
A telephone apparatus which allows a wired or wireless telephone subscriber to change a call forwarding telephone number at a remote location, and a call transfer method therefor. The call transfer method includes: receiving a call from an external telephone; determining whether a caller of the external telephone is a valid user; receiving a call forwarding telephone number from the caller; and outputting a call transfer request signal and the received call forwarding telephone number to a switching system.
摘要:
The present invention provides an interference canceling method and the apparatus of a multi-mode subtraction type in asynchronous multipath channels of CDMA system, which cancel the interference based on the received signal power of each user (or path), which make the selected fingers keep participating in the subsequent cancellation processing with new (more cleaned) input signal, which do a scale factor's processing and a clipper's processing to make the tentative bit decision, which can select the proper interference canceling method among various interference canceling method according to the total number of users in service, the hardware speed to implement the present method and the power spread of received signals, which repeat the selected interference canceling process recursively with a stage of hardware, which can reduce the number of stage compared with parallel interference cancellation method of the prior art in case that the interference canceling apparatus is made up multi-stages, which do overlappingly a canceling process of the last bit of the multiple bits for efficient operation in the asynchronous channel, which reduce the interference according to the power sequence of each multipath signal instead of the power sequence of each user signal made up multipath signals for efficient operation in multipath channels with unequal powers, which can increase the performance and capacity of the CDMA system by reducing the interference produced by a multiple access process in CDMA system with the asynchronous multipath channels.