50 results about "Cdma channels" patented technology

In a code division multiple access (CDMA) communications system including one or more terminals (such as customer premise equipments, CPEs) that communicate with a node (such as an Internet gateway) via at least a random access channel and a reservation-oriented channel, various schemes of managing communications traffic among the channels are provided. Decisions as to the channel on which a given terminal may transmit may be based on: traffic statistics (such as packet size or average data rate over a time period), traffic content (such as packet type), the terminal's output buffer loading (queue state, or “Q-state”), a history of the terminal's output buffer loading (one or more Q-states), and so forth. In one application, decisions in managing traffic in a live user's web browsing sessions may involve intelligent ascertainment of whether a given terminal is busy based on traffic analysis or output buffer loading.

A method and system for providing acknowledgment and / or data rate control (DRC) information with respect to data packets conveyed on a plurality of active forward link (FL) carriers. The number of reverse link (RL) carriers employed for the acknowledgment and / or DRC information may be less than the number of active FL carriers, and may be a single carrier, even when the signaling protocol is, in the limit, consistent with presently-supported standardized CDMA protocols. Code multiplexing techniques are employed inventively to convey information for up to fifteen FL carriers on a single, standard CDMA channel designed to provide such signaling for only a single FL carrier at a time.

A system, method, and receiver for receiving radio signals modulated according to different radio communication standards. Radio signals are received and downconverted to an intermediate frequency (IF) signal. An A / D-converter samples the IF signal at a sampling rate and digitizes the sampled signal into a digital signal. A channelizer filters out at least two modulated channels from the digital signal. A first ago channel is modulated according to a Time Division Multiple Access (TDMA) standard, and a second channel is modulated according to a Code Division Multiple Access (CDMA) standard. A first demodulating unit demodulates the TDMA channel, and a second demodulating unit demodulates the CDMA channel. Each of the demodulating units detects and, when needed, resamples each of the modulated channels individually, and delivers a corresponding demodulated channel. A Frequency Division Multiple Access (FDMA) channel may also be received and processed.

In one embodiment, a multi-carrier CDMA network grants radio link resources to a mobile station by maximizing soft handoff conditions, by preserving frequency continuity with the mobile station, or by load balancing across carrier frequencies in two or more cells, or by some combination thereof. The network identifies carrier frequencies having two or more CDMA channels for assignment to the mobile station. If one of those frequencies was used by the mobile station to request resources, it may be advantageous to select that frequency; otherwise or instead, the choice is narrowed to the carrier frequency or frequencies having the greatest number of available radio links. From that point, the choice may be further narrowed, for example, by selecting the carrier frequency having the most favorable CDMA channel loading across two or more cells. In another embodiment, such multi-carrier load balancing is the basis of carrier frequency selection.

A method and device of sending and receiving encoded media over a CDMA channel. A plurality of speech frames are output by a media codec, and the plurality of encoded media frames are encapsulated into a packet of a first type. The packet of the first type is encapsulated into a datagram of a second type. The datagram of the second type is encapsulated into a datagram of a third type. The datagram of the third type is divided into a plurality of equal-sized pieces, such that each of the equal-sized pieces fits to a specific CDMA channel frame. Each of the CDMA channel frames is sent over a CDMA air interface, and received at a receive end over the CDMA air interface.

Provided is a method and apparatus for acquiring time information from a CDMA system in a mobile communication terminal. The method includes: searching for a CDMA channel in a predetermined manner when a CDMA modem or module is activated; receiving a sync channel signal via the searched CDMA channel and extracting time information from the sync channel signal; and setting a time of the mobile communication terminal using the extracted time information. Therefore, even when the mobile communication terminal communicates with a system that does not provide time information, the mobile communication terminal can precisely maintain its time by acquiring time information from a CDMA system.

A CDMA network dynamically generates hard handoff (HHO) target sets to support mobile station HHO. Dynamically identifying CDMA channels or cells as targets for HHO eliminates the need for statically configured HHO target sets. In an exemplary embodiment, a source BSS identifies a first set of channels corresponding to common neighbor cells of the cells associated with the active set pilots and / or reported PBU pilots. This first set may be adjusted by removing any common neighbor cells that include soft handoff target channels, and by adding selected vertical neighbor channels of the active set pilots and / or reported PBU pilots. Channels in the first set may be grouped by carrier frequency and evaluated based on CDMA channel type, BSS affiliation and characteristics, and the target's relationship to the active set to identify a preferred HHO target set. Such operations permit dynamic determination of whether to perform inter- or intra-BSS HHO.

The invention relates to the technical field of CDMA wireless video-audio transmission, specifically to a wireless mobile audio-video transmission system. The system comprises a monitoring system of a command and control centre for multiplex transmission, display, storage and remote control of a remote audio-video, and a wireless video-audio transmission system for transmitting video images and sound signals in real time to the command and control centre by binding 4 or more than 4 (8-16) CDMA / EDGE / 3G wireless links. The system further comprises a vehicular wireless video-audio terminal for 4 CDMA channels to transmit audio-video in real time, to record image and sound locally with high definition, and to echo the image and sound locally with high definition. Through practical test, the system uses 4 CDMA links (4 caloric units) to realize a transmission rate of 300-450K / S at most, to smoothly transmit a CIF image (352*288) at a speed of 25 frame / S and to smoothly transmit audio signals.

Aspects of a method and system for servicing a plurality of users via a plurality of femtocells are provided. In this regard, a cellular enabled communication device may receive portions of a datastream from a plurality of femtocells, reconstruct the datastream from the received portions of the datastream, and process the reconstructed datastream for presentation to a user of the cellular enabled communication device. The received portions may be buffered in the cellular enabled communication device. The portions of the datastream may be associated with a plurality of CDMA channel access codes. The portions of the datastream may be received via a plurality of cellular frequencies. The portions of the datastream may be received during a plurality of TDMA timeslots. Portions of the datastream may be received from a cellular base station. Portions of the datastream may be received from a WiMAX base station.

A mobile station for use in an IS-2000-compatible wireless network. The mobile station is capable of receiving data from a first base station of the wireless network simultaneously in a first code division multiple access (CDMA) channel and a second CDMA channel. The mobile station transmits a capability message to the first base station, the capability message comprising a field indicating that the mobile station is capable of simultaneously operating in a Forward Packet Data channel (F-PDCH) and a Forward Supplemental channel (F-SCH).

This invention is about a method to reduce the near-far effect in the physical and media access control (MAC) layer for focusing on CDMA radio technologies in ad-hoc network systems. The radio resource is first organized and separated into small pieces, divided in both frequency domain (FDMA) and in time domain (TDMA). Each radio resource is considered as a physical radio channel (PRC). Any node in the network can dynamically allocate it. The near-far effect will be mitigated in each PRC, which is used for supporting a set of CDMA based sub-channels. The selection of the TX and RX PRC depends on which small geographical area (SGA) the node is located. As the nodes in the same SGA share the same PRC as the preferred and designated receiving PRC, power control is possible in a neighborhood of multiple SGA. Each SGA is viewed as a virtual base station regarding a designated PRC as the uplink channel. And each PRC provides a multiple sub-channels via the CDMA method. Adopting this Listening Frequency and Resource Planning (LFRP) can substantially increase the ad-hoc network capacity, by limiting the near-far effect in CDMA channels.

A mobile station for use in an IS-2000-compatible wireless network. The mobile station is capable of receiving data from a first base station of the wireless network simultaneously in a first code division multiple access (CDMA) channel and a second CDMA channel. The mobile station transmits a capability message to the first base station, the capability message comprising a field indicating that the mobile station is capable of simultaneously operating in a Forward Packet Data channel (F-PDCH) and a Forward Supplemental channel (F-SCH).

The invention provides a method and a device for terminals to select resident CDMA channels. CDMA channels configured on a base station is divided into at least two CDMA channel groups, wherein each CDMA channel group is used for supplying service for terminals with different priority levels, and the base station is used for determining that all the CDMA channels of a paging channel or a broadcast control channel are configured in each CDMA channel group. The method for terminals to select resident CDMA channels comprises the following step of: broadcasting a channel list message in the coverage area of the base station by the base station through all the CDMA channels of the paging channel or the broadcast control channel configured in each CDMA channel group, wherein the channel list message comprises channel marks of all the CDMA channels in each CDMA channel group, which are configured with the paging channel or the broadcast control channel, so that the terminals with different priority levels can select the resident CDMA channels in the CDMA channel groups.

The invention provides a training sequence variable step-size least-mean-square algorithm, in particular to a training sequence quick channel estimation method. Employing factors which are capable of adaptively tracking and controlling the changes of characteristic parameters through error estimation, the quick channel estimation method improves the convergence speed of the algorithm and acquires the weight coefficient of an optimum filter speedily. The invention discloses a training sequence least-mean-square characteristic parameter estimation method which is quicker in convergence speed and more precise than prior art. The method is easy to realize and is applicable in communication systems for modulated orthogonal frequency division multiplexing for channel estimation. Meanwhile, the idea of the invention can be applied to CDMA channel estimation devices and TDMA channel estimation devices, and can also be applied to LMS methods and the derivative methods thereof. The channel estimation method relates to the fields of communication, oil and seismic exploration, sonar, image processing, computer vision, biomedical engineering, vibration engineering, radar, remote control and telemetry, as well as aerospace field.

Provided is a method and apparatus for acquiring time information from a CDMA system in a mobile communication terminal. The method includes: searching for a CDMA channel in a predetermined manner when a CDMA modem or module is activated; receiving a sync channel signal via the searched CDMA channel and extracting time information from the sync channel signal; and setting a time of the mobile communication terminal using the extracted time information. Therefore, even when the mobile communication terminal communicates with a system that does not provide time information, the mobile communication terminal can precisely maintain its time by acquiring time information from a CDMA system.

A multi-carrier transmitter capable of transmitting on one or multiple frequency channels simultaneously is described. In one design, the multi-carrier transmitter includes at least one processor and a single radio frequency (RF) transmission chain. The processor(s) may generate output chips for each of multiple frequency channels, digitally filter and upsample the output chips for each frequency channel to obtain filtered samples, and digitally upconvert the filtered samples for each frequency channel to a different frequency to obtain upconverted samples. The processor(s) may then combine the upconverted samples for the multiple frequency channels to obtain composite samples, perform pre-distortion on the composite samples for I / Q mismatch compensation, and upsample the pre-distorted samples to obtain output samples. The output samples may be converted to an analog signal with a wideband DAC. The RF transmit chain may process the analog signal to generate an RF output signal.

Parallel interference cancellers are connected in successive stages. In each canceller, multiple signal paths are provided for interference replica estimators to receive multiple CDMA channels. A spread code is generated for each signal path for dispreading the path components of the channel. In each signal path, the despread components are RAKE combined and a symbol replica is detected therefrom either by detecting or estimating the type of modulation. The detected symbol replicas are re-modulated and then re-spread to produce interference replicas. In each stage, the interference replicas are summed and subtracted from a delayed CDMA signal and then summed with the interference replicas of the same stage. Output signals from the final stage are despread and symbol replicas are recovered therefrom. For each signal path, a spread code is detected from a control channel and compared to the generated spread code. Those symbol replicas where a coincidence is detected are supplied to respective decoders and diversity combined.

The invention provides an electric energy collecting and running management system on the basis of a station area concentrative service terminal, and a method thereof. The electric energy collecting and running management system is provided with a master system, a station area concentrative service terminal, an electric energy meter collector, a station area electric energy meter and a resident electric energy meter; the master system is in charge for services such as data collecting, processing, managing and analysing, output and the like; the running state of the system is monitored and undated; two communication channels such as GPRS or CDMA and RS232 are used between the master system and the station area concentrative service terminal; the station area concentrative terminal has the functions of distribution transform monitoring, electric usage site management, meter concentrator meter reading and the like; the downlink selects a RF narrowband wireless radio frequency data transmission / power carrier / RS483 interface to be communicated with the electric energy meter collector; meter reading task is sent down to the electric energy meter collector; the terminal collects the electric meter information read by various collectors and analyses all electric meter information; and the uplink transmits all data to the master system by the GPRS / CDMA channels.

An overhead message and a method of performing channel hashing using the same are provided. The overhead message includes first and second fields of an extended CDMA channel list message (ECCLM). The first field contains information indicating whether the ECCLM includes at least one frequency assignment of list of frequency assignments that allows packet data support for a forward packet data channel or a 1×EV-DV system and the second field indicates whether each frequency assignment allows such support, thereby enabling channel hashing to be performed by a packet-data-supportable mobile station of a communication system.

A system and method for determining 1xEV-DO availability for a packet data call in a wireless device is presented. When the wireless device receives a request to initiate a packet data call, the device determines if it currently has access to a preferred 1xEV-DO channel. The determination can be made by consulting a 1xEV-DO availability list stored in persistent memory on the wireless device. If available, the wireless device originates the packet data call on the 1xEV-DO channel. If the device is using a CDMA system that has 1xEV-DO channels but the availability or usability of those channels are unknown, the device polls the signal strength on the 1xEV-DO channels to determine the best 1xEV-DO channel to use for the packet data call. If no 1xEV-DO channel is available or if none of the available 1xEV-DO channels are usable, then the device originates the packet data call on a CDMA channel.

The present invention is a novel and improved method for monitoring the real time loading condition in a CDMA wireless communication system. The level of the power control signal is obtained by monitoring, in real time, at the base station the forward link CDMA channel, comparing this measurement to the previously obtained level, and displaying the level of the power control signal as a line which can consist of two parts. The first part can be a solid line the length of which represents the level of the power control signal in real time and the second part can be a dotted line whose length increases slowly and decreases rapidly to indicate that the level of the power control signal is rising. Conversely, a rapid increase and a slow decrease of the length of the dotted line indicates that the level of the power control signal is falling. Color coding can be used to indicate that the level of the power control signal is at or outside an optimum operating range.

Disclosed is a method for operating a CDMA channel in a base transceiver station (BTS). The method for operating the CDMA channel in the BTS includes variably generating a CDMA channel list message transmitted from the BTS to a mobile station (MS) in a CDMA mobile communication system according to the BTS and a frequency allocation (FA) within the BTS, so as to variably operate the CDMA channel by the BTS and the FA. The method according to an embodiment of the present invention also includes variably allocating a CDMA frequency number group by the BTS and the FA in accordance with a CDMA channel index, a CDMA channel ID, and a CDMA channel kind, so that the CDMA channel is operated between BTSs and further by the FA, independently, thereby optimizing the CDMA frequency operation between the BTS and the MS.

The invention relates to an on-line monitoring system for a transformer substation. The on-line monitoring system comprises a distribution monitoring terminal, a GSM / CDMA channel and a background server, wherein the distribution monitoring terminal is used for acquiring and recording data; the GSM / CDMA channel is used for performing remote data transmission; and the background server is used for performing trend analysis on the acquired and recorded data and maintaining the distribution operation according to the trend analysis result. The acquired data comprises three-phase current, three-phase voltage, active power, passive power, active electric quantity, passive electric quantity, three-phase total active electric quantity, total passive electric quantity, maximum value and minimum value of current and occurrence time of each data. The recorded data comprises historical record of voltage exceeding upper limit and lower limit, historical record of overload current and historical record of open phase and current loss. Through the system, the trend analysis is performed on the acquired and recorded data and the distribution operation is maintained according to the trend analysis result, so that the efficiency of monitoring the distribution operation is increased, the distribution operation is maintained in time, the maintenance timeliness is improved, and the like.

The invention discloses a mine laneway uplink time frequency coded cooperation MC-CDMA channel estimation method. The method comprises the steps that firstly, a mine laneway uplink time frequency coded cooperation MC-CDMA data transmission frame with pilot frequency is formed, and the pilot frequency sequences of users are different time delay ectypes of the same pilot frequency sequence. According to the pilot frequency design method, the pilot frequency sequences of the users can be staggered by the length of an MC-CDMA symbol cyclic prefix on the time domain, interference among the users is avoided, and the pilot frequency MC-CDMA symbols of the users can be arranged at the same position in one frame; then, channel estimation is carried out through the received pilot frequency sequences of the users on a base station or a collaborative partnership side, and the estimated value of the gains of a channel corresponding to a subcarrier of each user is obtained. Through the algorithm, the interference among the users can be avoided, and meanwhile the pilot frequency resource utilization ratio can be improved as much as possible.

System and method are provided for redirecting a communication device between a macro network and a femtocell network using a service redirection message (SRDM). In an embodiment, the communication device registers with the network which then determines the subscription status of the communication device to a femtocell network. If the subscription is confirmed, using the SRDM the system redirects the communication device to a communication frequency used by the femtocell network. Upon receipt of the SRDM, the communication devices tunes to a communication frequency specified in the SRDM. The system may segregate the CDMA channels used by the macro network, one set containing channels exclusive to the macro network and the other containing channel or channels used by both the macro network and the femtocell network. In this way, the communication device is prevented from entering a frequency re-hashing loop.

A method and device of sending and receiving encoded media over a CDMA channel. A plurality of speech frames are output by a media codec, and the plurality of encoded media frames are encapsulated into a packet of a first type. The packet of the first type is encapsulated into a datagram of a second type. The datagram of the second type is encapsulated into a datagram of a third type. The datagram of the third type is divided into a plurality of equal-sized pieces, such that each of the equal-sized pieces fits to a specific CDMA channel frame. Each of the CDMA channel frames is sent over a CDMA air interface, and received at a receive end over the CDMA air interface.

A method is provided for reduced interference between S / CDMA channels (chips) by selecting a first sequence of spreader functions for a first channel, and selecting a second sequence of spreader functions for a second channel, wherein said second sequence is non-overlapping with and spaced from first said sequence.