543 results about "Spreading factor" patented technology

A method of managing processing resources in a mobile radio system, in which a first entity manages radio resources and corresponding processing resources, the latter being provided in a second entity separate from the first entity, in which method: the second entity signals to the first entity its global processing capacity, or capacity credit, and the consumption law, or quantity of said global processing capacity, or cost, for different spreading factor values, the first entity updates the capacity credit on the basis of the consumption law, and in the case of multicode transmission using N spreading codes, said updating is effected on the basis of the cost for at least one of the N spreading codes.

A method of adaptive Walsh code allocation in a wireless communication system. The method includes the step of each voice user transmitting quality condition signal, such as a pilot signal strength measurement to a corresponding base station. Upon receiving each quality condition signal, the method includes determining a spreading factor for each voice user in response to its quality condition signal. A Walsh code is thereafter allocated to each voice user in response to the determined corresponding spreading factor. Thus, for example, if the quality condition signal of a first voice user is relatively higher than the quality condition signal of a second voice user, the spreading factor allocated to the first voice user should be longer than the spreading factor of the second voice user.

The CDMA communication device of the present invention includes a spreading unit, radio transmitters, and a control device that includes a setting unit and a determination unit. The spreading unit spreads and multiplexes user data of users. The radio transmitters are provided correspondingly to each of a plurality of frequencies, and modulate with the corresponding frequencies the user data that are supplied from the spreading unit. The determination unit determines the working frequency of users based on the spread factor value of the user data. The setting unit sets the spread factor of the user data in the spreading unit. The setting unit further performs setting of the spreading unit such that user data that have undergone spreading are supplied to the radio transmitter that has been provided correspondingly to the frequency determined by the determination unit.

An orthogonal variable spreading factor (OVSF) of one dimension represented by coding tree is extended into two dimensions and applied simultaneously in both directions, frequency axis direction and time axis direction when carrying out spreading of two dimensions of frequency axis direction and time axis direction. For example, the transmission data is first spread by OVSF code of one dimension in the frequency axis direction (obtained from frequency axis direction OVSF code assignment section 11), and the result is spread by OVSF code of one dimension in time axis direction (obtained from time axis direction OVSF code assignment section 13, which is selected independent of frequency axis direction) in each of two-dimensional spreading sections 1-1 to 1-8.

Disclosed is a method and apparatus for providing uplink packet data services through an E-DCH in an asynchronous WCDMA system. A transport block size (TBS) for transmitting uplink transport channel data is determined. A combination of a spreading factor and a modulation scheme for uplink channel data transmission, corresponding to the determined TBS, is selected according to transmittable physical channel data bit sizes and puncturing limit values. The TBS is transmitted by incorporating it into control information of the uplink transport channel data. The modulation scheme and spreading factor combination is determined based on a physical channel data bit size that maximizes transmission efficiency and minimizes the number of punctured bits, without requiring an additional physical channel in transmitting the uplink data having the TBS. This method maximizes uplink transmission efficiency to save transmission resources and reduces signaling overhead required to transmit E-DCH control information.

For a bandwidth extension of an audio signal, in a signal spreader the audio signal is temporally spread by a spread factor greater than 1. The temporally spread audio signal is then supplied to a demicator to decimate the temporally spread version by a decimation factor matched to the spread factor. The band generated by this decimation operation is extracted and distorted, and finally combined with the audio signal to obtain a bandwidth extended audio signal. A phase vocoder in the filterbank implementation or transformation implementation may be used for signal spreading.

A connection controlling method of integrating a time synchronous code division multiple access with a automatic-organizing network belongs to the mobile communication field of the communication technology, based on keeping the unitive air interface of TD-SCDMA honeycomb network physic frame invariable construction, the method is a multi-channel synchronization connecting control method based on the preset pattern and distributing pattern control, the time span resource is divided into the control channel and the data channel by the OVSF (Orthogonal Variable Spreading Factor), thus improving the time span reusability through terminal to terminal status to expose the terminal problem, the method maintains the time span status of node within two jumps time span, and realizes the conflict-free wireless connection within two jumps time span; thereby solving the problems of realizing the conflict-free visit time span and performing the reliable alternation communication under integrating network and multi-communication modes.

A reception method and receiver structure that are relatively simple, that have close to optimum performance, and that use high order modulation combined with a low spreading factor are disclosed. The method receives a signal transmittal in the form of sequences of coded binary symbols comprising both predefined pilot symbols and date symbols multiplied by a spreading sequence. The method also includes a step of determining a channel estimate using received predefined pilot symbols. A system for receiving a signal transmitted on a multipath transmission channel using a spread spectrum technique and low spreading factor is also disclosed.

An apparatus and method are provided for transmitting high-speed data through a plurality of transmitter antennas using a relay network, receiving signals transmitted from the plurality of transmitter antennas, and removing interference in a mobile communication system. The received signals are despread on a transmitter antenna-by-transmitter antenna basis according to a preset spreading factor. The despread signals are divided into data signals and noise. The signals transmitted through the plurality of transmitter antennas are regenerated from recovered data signals. Data components and interference signal components are identified. The interference signal components are removed from the signals transmitted on the transmitter antenna-by-transmitter antenna basis.

A MC-CDMA handset has a receiver (30) that estimates SIR based on a spread factor of a pilot channel. More particularly, a spread spectrum signal including a pilot channel and multiple data channels is received. The pilot channel is despread using a spread factor (SF). The SIR for the despread pilot channel is calculated and stored in a memory (34). The SF is then incremented and used to despread the pilot channel again, and this process is repeated for all of SF. The stored SIRs are compared to a threshold value in ascending order of the SFs. The first SIR value to fall below the threshold value is used as the estimated SIR result.

Embodiments of the present invention include a method for performing joint time synchronization and carrier frequency offset estimation in a wireless communication system, comprising steps of: on a transmitter: performing frequency domain spreading and interleaving on input data by using a predetermined spreading factor (SF) to generate a frequency domain training symbol; performing Inverse Discrete Fourier Transformation (IDFT) on the generated frequency domain training symbol to generate a first time domain training symbol; reversely copying the generated first time domain training symbol to a second time domain training symbol such that a complete training sequence is formed; and on a receiver: detecting an average power of received signals to judge the coming of a training sequence, and performing coarse frame synchronization; performing joint fine frame synchronization and carrier frequency offset estimation based on a received training sequence; and compensating for the carrier frequency offset based on the carrier frequency offset estimation result so as to eliminate the carrier frequency offset. In addition, embodiments of the present invention also include an apparatus for performing joint time synchronization and carrier frequency offset estimation and a method for generating a training sequence.

Aspects of a method and system for a variable spreading factor Walsh Hadamard Transform engine are presented. Aspects of the system may include a variable spreading factor Fast Walsh Hadamard Transform engine that enables spread spectrum encoding of data from each of a plurality of data sources. A plurality of spreading factors may be utilized wherein at least 2 of the plurality of spreading factors differ. The variable spreading factor Fast Walsh Hadamard Transform engine may enable combination of a plurality of spread spectrum encoded data to form a data vector.

A transmitter (200) used in a wireless communication system based on an orthogonal frequency division multiplexing (OFDM) scheme includes a determination unit (216) configured to determine a spreading factor and an amplitude for a control channel based on at least one of signal quality information and interference information in data transmission, a multiplexing unit (212) configured to multiplex a data channel with the control channel having been code-spread based on the spreading factor and the amplitude, and means (214) configured to modulate the multiplexed signal in the OFDM scheme and transmit the modulated signal as OFDM symbols.

In a UMTS network in which a single user can transmit or receive a number of services having different transmission power requirements over a single channel, a method of determining for each service the number of bits to be punctured or repeated to provide rate matching by the steps of deriving for each service the Energy per Bit per Noise density EB/NO required to achieve a desired Bit Error Rate; from each EB/MO deriving a value of the Energy per coded Symbol per Noise density ES/NO; and from ES/NO deriving a rate matching factor by which that ES/NO can be matched to the minimum Energy per coded Symbol per Noise density applicable to the channel in which to the services are multiplexed. The values of EB/NO are stored in a look up table in the BTS and each mobile; the BSC generates values of semi static rate matching factors and spreading factors for each service and transmits them to the BTS and mobiles so that the mobile can calculate from the received values and the values stored in the look up table the number of bits to be punctured or repeated.

This invention discloses a method for distributing resources in down packet data transmission by increasing HS-PDSCH with the spread-spectrum factors greater than 16 and setting up a corresponding relation between the CQI value corresponding to the increased HS-PDSCH and the transmission block, numbers of the HS-PDSCH channels and a modulation mode including: the base station searches for all corresponding relations based on the CQI value fed back by the UE and the due sent data volume to configure the transmission block, HS-PDSCH channel numbers and a modulation mode for the UE.

A method of noise factor computation for a chip equalizer in a spread spectrum receiver, the method including the steps of: computing channel and noise variance estimates for multiple resolvable fading paths of chip signals received at the spread spectrum receiver; computing the sum of power of the channel estimates; estimating the chip energy of the chip signals; and computing the noise factor from the chip energy estimate, channel and noise variance estimates, sum of power of the channel estimates, and spreading factor of the pilot signal.