Showing papers by "Huawei published in 2000"

Apparatus and method for packet scheduling

Abstract: In a network router, a tree structure or a sorting network is used to compare scheduling values and select a packet to be forwarded from an appropriate queue. In the tree structure, each leaf represents the scheduling value of a queue and internal nodes of the structure represent winners in comparisons of scheduling values of sibling nodes of the tree structure. CBR scheduling values may first be compared to select a queue and, if transmission from a CBR queue is not timely, a packet may be selected using WFQ scheduling values. The scheduling values are updated to reflect variable packet lengths and byte stuffing in the prior packet. Scheduling may be performed in multiple stages.

An integrated system for prediction and analysis of solder interconnection shapes

Abstract: In this paper, an integrated system [predicting solder interconnection shapes (PSIS)] is built to predict and analyze the shape of solder interconnections in electronic packaging. The purposes are to numerically simulate the formation of solder joints, analyze the shape of solder joints and its influential factors and provide an efficient tool for design and manufacturing engineers to improve the integrity of solder interconnections. The formation of solder joints is numerically simulated through a surface evolver program and the calculation is automated with an additional controller. A datafile generator is developed in which the potential energies, geometry of the conjunction and boundary conditions of the initial solder joint can be generated visually and transferred into evolver syntax automatically. A post processor is built to analyze the global three-dimensional (3-D) shape and cross section profiles of solder fillets. Also, the applications for solder interconnection shape prediction of chip component (RC3216) are conducted with this system.

Implementing method for adding monetary value of mobile prepayment service in different locations

Abstract: An implementing method for adding monetary value of mobile prepayment service in different locations by an intelligent network is disclosed. In the method, an SDP of intelligent network is separately located outside of an SCP, and all data of monetary value added cards of mobile prepayment service are memorized in said SDP. When a user of the mobile prepayment service dials the monetary value added service access number to perform monetary value added operation, the call is accessed to an SSP. The SSP analyses the calling number of the call, determines its home SCP, and triggers an intelligent call to its home SCP. The entire monetary value added process is controlled by the home SCP, and by the interactive process between the home SCP and said SDP, the user data and the status of monetary value added card are modified. Implementing the method of present invention can reduce the complexity of engineering techniques, data management and statistics, and make the intelligent network easy to expanding.

Photonic switch using time-slot interchange

Abstract: An optical data stream is converted to electrical signals which are applied to a time-slot interchanger. The time-slot interchanger reorders the packets or cells of the data stream to correspond to the schedule of an optical switch. The time-slot interchanger may contain a plurality of FIFOs implemented as circular buffers in a single dual port memory. The switch schedule may be determined by the average load between inputs and outputs and may be determined by the number of packets or cells queued from each input or each output in the time-slot interchangers.

Wideband CDMA mobile equipment for transmitting multichannel sounds

Abstract: The present invention discloses a wideband CDMA mobile equipment capable of transmitting real-time bi-directional multichannel sound, which can be used in mobile station, handset or vehicle station. It comprises sending unit, receiving unit, central processing unit (CPU) and duplexer both connecting with the said sending and receiving unit. In the sending unit the stereo source is encoded into data stream, emitted after modulated by broadband CDMA into the prescriptive radio communication frequency range. In the receiving unit the radio signal carrying stereo is received with wideband CDMA and restored into digital code stream, then decoded into high quality of stereo sound. In combination of image encoding, the mobile communication system can provide not only bi-directional voice service, but also the services of the high quality of music or multichannel sound and image.

The nonlinear model of A2PI magnetic field sensor

Abstract: In order to get better performance and higher design efficiency, the output of an amorphous alloy pulse-induced (A2PI) magnetic field sensor must be predicted and analyzed, so it is necessary to model the sensor. The transient process of the sensor probe was studied thoroughly. A nonlinear model based on equivalent electrical circuit techniques was developed. The nonlinearity of the model, which mainly comes from the use of amorphous alloy as core material, was solved by parameter identification and in-depth mathematical analysis. The simulation results of the equations show good agreement with the experimental results. This analysis is valuable for optimization of this kind of magnetic field sensors.

Performance evaluation of a three-stage packet switch with internal speedup and independent routing

Abstract: The performance of a three-stage Clos-like packet switching fabric is evaluated. With the switching fabric architecture, the switching element of the first-stage and the third-stage both have shared memory buffering, and the switching element in the second-stage is bufferless. In order to achieve better performance/complexity characteristics, several operations are adopted: internal speedup, independent routing, and buffer backpressure control between switch interfaces and switching fabric. Under the uniform traffic model, the effect of speedup factor and buffer size on the performance of this switching fabric is analyzed, and some conclusions are given.

A speed estimation based two-stage symbol aided channel estimator for frequency nonselective variant fading channel

Abstract: In this paper, we propose an algorithm for tracking the phase and amplitude of frequency nonselective fading channels. In contrast to conventional channel estimation techniques, which do not take enough advantage of the statistical characteristics of the received radio signal, this algorithm combines a conventional channel estimator with a speed estimator which can adaptively control the mode of the interpolation technique, the bandwidth of the smoothing filter or the step length of the adaptive filter (e.g. the LMS algorithm) in order to track the variant fading channel. Simulation results demonstrate the improved performance of this algorithm compared with the conventional channel estimator under the variant fading channel.

Wide band movable CDMA equipment capable of transmitting multichannel sound

Abstract: The present invention discloses a wideband CDMA mobile equipment capable of transmitting real-time bi-directional multichannel sound, which can be used in mobile station, handset or vehicle station. It comprises sending unit, receiving unit, central processing unit (CPU) and duplexer both connecting with the said sending and receiving unit. In the sending unit the stereo source is encoded into data stream, emitted after modulated by broadband CDMA into the prescriptive radio communication frequency range. In the receiving unit the radio signal carrying stereo is received with wideband CDMA and restored into digital code stream, then decoded into high quality of stereo sound. In combination of image encoding, the mobile communication system can provide not only bi-directional voice service, but also the services of the high quality of music or multichannel sound and image.

Method of transmission of image by CDMA system

Abstract: This invention discloses an image transmission method, which keeps the quality of the image transmission unchanged and increases the capacity for code division multiple access (CDMA) mobile communication system. By applying the subband coding with threshold method and differential perspective coding method, which change the image compression ratio and coding rate according to the characteristics of the image, the image transmission quality keeps unchanged. By changing the spread spectrum factor and adjusting the emission power accordingly or by applying the discontinuous emission mode without changing the spread spectrum factor, the purpose of increasing CDMA system capacity is reached.

A pilot synchronous channel structure for mobile communication systems

Abstract: The present invention discloses a pilot synchronous channel structure for mobile communication system, which superimposes a pilot channel on the synchronous channel (SCH) defined in Wideband Code Division Multiple Address (WCDMA) protocols. Every frame of the pilot channel is composed of a plurality of time slots, every time slot is filled with spreaded and discrambled predetermined pilot symbols. The superimposing can be either an intermittent superimposing of search code with the size of one symbol and pilot signal with the size of m-1 symbols, or a continuous superimposing of search code with the size of one symbol and pilot signal with the size of m symbols. The present invention dynamically combines CDMA2000 with WCDMA, and better functions as pilot and synchronization.

Wcdma mobile device of transmissible multi-channel sounds

Abstract: The invention discloses a wideband CDMA (WCDMA) mobile device being able to two-way transmit multi-channel sounds in real-time, for using in mobile stations, handsets and vehicle stations. It comprises a transmitting unit for multi-channel sounds, a receiving unit for multi-channel sounds, a central processing unit connecting with the transmitting unit and the receiving unit, and a duplexer. The transmitting unit encodes a stereo source into a data code stream, and modulates it in a WCDMA modulator onto a specified radio communication band in order to transmit. The receiving unit performs WCDMA reception on radio signals containing stereo sounds, recovers the digital code stream and decodes speech signals into high quality stereo sounds. By image encoding, mobile communication systems are made further to provide high quality music or multi-channel sound and image services while providing two-way speech services.

Wcdma mobile device for transmitting multichannel sounds

Abstract: The invention discloses a wideband CDMA (WCDMA) mobile device being able to two-way transmit multi-channel sounds in real-time, for using in mobile stations, handsets and vehicle stations. It comprises a transmitting unit for multi-channel sounds, a receiving unit for multi-channel sounds, a central processing unit connecting with the transmitting unit and the receiving unit, and a duplexer. The transmitting unit encodes a stereo source into a data code stream, and modulates it in a WCDMA modulator onto a specified radio communication band in order to transmit. The receiving unit performs WCDMA reception on radio signals containing stereo sounds, recovers the digital code stream and decodes speech signals into high quality stereo sounds. By image encoding, mobile communication systems are made further to provide high quality music or multi-channel sound and image services while providing two-way speech services.