33 results about "Rake reception" patented technology

A method and apparatus for determining operating modes in a receiver is described herein. A delay searcher in the receiver detects a signal image in the received signal. When the receiver is a RAKE receiver, a plurality of RAKE fingers coherently combine time-shifted versions of the received signal at different delays. Alternatively, when the receiver is a chip equalization receiver, an FIR filter coherently pre-combines the signal images in the received signal. A processor determines delays. In particular, the processor generates a first signal quality metric for a single-delay receiver mode, and generates a second signal quality metric for a multi-delay receiver mode. Based on a comparison of the first and second signal quality metrics, the processor selects the single-delay or the multi-delay receiver mode for processing the signal image.

The present invention can eliminate the multipath effect, channel interference and Doppler effect in mobile communication. The reception method includes the direct treatment of the received RF baseband signal with filter, multiplier and preset data and the direct feeding of the treated signal to the software adjudication decoder. The RAKE receiver of the present invention consists of matching filter, delay search tracker, predicting filter, smoothing filter, delay regulator, multiplier, multipath adder, filter parameter data base, S / N measuring comparator and one-out-of-three selector.

A radio communication apparatus which is used in a CDMA communication system, has a plurality of fingers, and performs rake reception, includes a delay profile calculating section and a finger path allocating section. The delay profile calculating section calculates a delay profile using a reception signal. The finger path allocating section allocates path positions to the plurality of fingers on the basis of the delay profile calculated by the delay profile calculating section. A delay profile calculation cycle in the delay profile calculating section is variable. A power consumption control method is also disclosed.

To provide an apparatus which reduces the scale of a reception circuit and the power consumption as the tracking function of tracking phase jitter of the multipath propagation route. A RAKE reception apparatus includes a plurality of finger circuits for receiving signals spectrum-spread by spread codes, despreading respective reception signals retrieved by a searcher adapted for retrieving respective paths from multipath reception signals for demodulating the signals, and a RAKE combiner for combining outputs of the plural finger circuits. Each of the plural finger circuits is provided with one DLL circuit without being provided with an inner DLL circuit. The finger circuits to be tracked by the DLL circuit are switched by a changeover circuit. There is provided a control circuit for controlling the changeover circuit based on the weighting information for each finger circuit to be found by the RAKE combiner for sequentially selecting the finger circuits to be tracked by the DLL circuit.

A wireless communication device and a method for selecting a receiving mode are used to improve the throughput of the entire system. A SIR measurement component (106) measures the SIR of a known signal. A Doppler frequency detection component (108) detects the Doppler frequency from the received signal to measure a Doppler shift, wherein the Doppler shift is an indication of the speed at which the mobile station device is moving. Interference power measuring means (110) measures interference power from different cells. Known signal acquisition section (104), SIR measurement section (106), Doppler frequency detection section (108), and interference power measurement section (110) constitute propagation environment estimation section in this embodiment. Based on the SIR, Doppler offset, and interference power, the reception method selection section (112) selects one of two reception methods, RAKE reception or linear equalization.

The invention in use for wireless communication includes following steps: obtaining estimated value of channel from data signals of received baseband signals in training sequence signals of spread spectrum communication system; picking up a sample signal in spread spectrum sequence cycle from the said data signal; carrying out conjugate transformation for initial spread spectrum sequence; multiplying the transformed spread spectrum sequence by the said sampled signal, and then carrying out FFT; multiplying obtained Kth value by phase exp(- jk2Pi / N) so as to obtain sliding correlation value between received signal and initial spread spectrum sequence; based on estimated value of channel, carrying out multidiameter combination for sliding correlation value. The transmission data are obtained from spread spectrum sequence corresponding to maximum among combined values. Advantages are: reducing amount of calculation in channel estimation and Rake reception, increasing flexibility.

A rake reception apparatus for determining whether a paging channel is received in a mobile terminal using a Discontinuous Reception (DRX) mode. A searcher searches for a multi-path signal using a received signal output from a Radio Frequency (RF) part, and calculates an energy value for each hypothesis. A demodulator demodulates a Paging Indicator (PI) for a hypothesis for which an energy value calculated by the searcher exceeds a valid path threshold. A controller determines whether a paging channel is received, according to the demodulated signal output from the demodulator, and performs finger allocation using a multi-path search of the searcher if it is determined that the paging channel is transmitted.

A transmitting apparatus 100 spreads broadcast information by means of a spreading section 103, limits the band of spread broadcast information by means of a band limiting filter section 104 so as not to overlap a guard frequency band, adds the output signal of a band limiting filter section 104 to transmit data after an inverse Fourier transform by means of an adding section 105, modulates the resulting signal by means of a modulation section 106, and transmits it. A receiving apparatus 150 passes only a signal in a guard frequency band by means of a reception filter section 154, demodulates it by means of a demodulation section 155, despreads it by means of a despreading section 156, and performs rake reception by means of a rake reception section 157 to obtain broadcast information. By this means, guard frequency bands can be used efficiently, and spectrum efficiency can be improved.

An object of the present invention is to provide a rake receiver and a receiving method for efficiently assigning paths to fingers in a CDMA mobile communication system. In the present invention, a correlation-value calculation section 2 calculates correlation values between spreading codes and reception signals input from an input terminal 1, at all timings at which rake reception is possible, and outputs the calculated correlation values to a delayed-profile creation section 3 and a difference-history creation section 6. The delayed-profile creation section 3 determines average correlation values and issues the values as a delayed profile to a path selection section 4. For each reception timing, the difference-history creation section 6 compares the latest correlation value issued from the correlation-value calculation section 2 with a previous correlation value held by the difference-history creation section 6, to determine a difference history, and issues the difference history to the path selection section 4. The path selection section 4 rearranges the delayed profile in decreasing order the average correlation values. When the delayed profile and the difference history satisfy all predetermined conditions, the path selection section 4 assigns the corresponding reception timing to a finger and issues the reception timing to the finger section 5.

The invention in use for wireless communication includes following steps: obtaining estimated value of channel from data signals of received baseband signals in training sequence signals of spread spectrum communication system; picking up a sample signal in spread spectrum sequence cycle from the said data signal; carrying out conjugate transformation for initial spread spectrum sequence; multiplying the transformed spread spectrum sequence by the said sampled signal, and then carrying out FFT; multiplying obtained Kth value by phase exp(- jk2Pi / N) so as to obtain sliding correlation value between received signal and initial spread spectrum sequence; based on estimated value of channel, carrying out multidiameter combination for sliding correlation value. The transmission data are obtained from spread spectrum sequence corresponding to maximum among combined values. Advantages are: reducing amount of calculation in channel estimation and Rake reception, increasing flexibility.

Monitoring is made as to whether the serial number of header incorporated to the data sent to a Radio Link Control (RLC) after a decoding process is continuous. When it is determined as a result of monitoring for a predetermined period of time that no defect is present in the header numbers, a multi-path timing is detected by taking a correlation between the result of the detection and spread codes of received signals and a pilot signal. From this multi-path timing, a station, from which data are to be received in fingers, is determined for interrupting processes of de-spread, RAKE reception and decoding, thus reducing power consumed in the processes.

A cellular radio communication system, a cellular radio communication method and a rake reception method for raising the efficiency of a baseband, and increasing the freedom of the structure of the radio base station. A cellular radio communication system comprises a baseband and first to Nth transmitter-receicvers connected by a transmission line. The baseband is provided with a modulator for producing, by a digital process, modulation signals to be sent from the first to Nth transmitter-receivers, and a demodulator for demodulating digital modulation signals received and analog-to-digital converted by the first to Nth transmitter-receivers. The transmitter-receiver is provided with a digital-to-analog converter for converting a digital modulation signal to a modulation signal to be sent, and an analog-to-digital converter for converting a received modulation signal to a digital modulation signal.

In order to support channels for the HSUPA standard, a base station number is given to each finger at the time of RAKE reception so that the base station numbers can be discriminated from each other, thereby allowing RAKE reception to be performed separately for each different base station. Since a function to identify a base station to which each finger is assigned is provided, data from a base station 0 and data from a base station 1 can be combined as data from different base stations and thus correct data for each base station can be received.

The present invention can eliminate the multipath effect, channel interference and Doppler effect in mobile communication. The reception method includes the direct treatment of the received RF baseband signal with filter, multiplier and preset data and the direct feeding of the treated signal to the software adjudication decoder. The RAKE receiver of the present invention consists of matching filter, delay search tracker, predicting filter, smoothing filter, delay regulator, multiplier, multipath adder, filter parameter data base, S / N measuring comparator and one-out-of-three selector.

A rake reception device capable of allocating an appropriate number of fingers to a channel. In this device, a selection control section sets a finger allocated to the channel from the channel communication state and a control signal based on this setting is output to a synchronization processing section and to a selection switch. According to the control signal, the synchronization processing section detects a path and a spread code phase in a reception signal and allocates the detected path to the finger which has been set. The finger which has been set de-spreads the signal of the path allocated and performs synchronous detection. According to the control signal, the selection switch switches the connection between the finger and a maximum ratio combination section so that the output from the finger is output to the maximum ratio combination section.

The invention discloses a pulse radio ultra-wideband RAKE receiving and judging method in a high-speed mobile environment, and aims to solve the technical problem that a conventional pulse radio ultra-wideband RAKE receiving and judging method is complex. According to the technical scheme, the method comprises the following steps: sending data information bits according to a block structure, sending a data block to a receiving end through a channel after pulse is shaped, and obtaining a template signal vd (t) of an RAKE receiver after the receiving end is subjected to channel estimation; according to estimated doppler dimension change factors, carrying out doppler compensation for the template signal vd (t), so as to obtain a new RAKE receiving template signal v (t); carrying out RAKE receiving and judgment, so as to obtain sent information. The method estimates the dimension change factors by inserting pilot signals among block signals, and then utilizes the dimension change factors to determine the influence brought by the fact that the template signal is repeatedly collected in a repeated collection cycle to compensate the dopper effect. The method is simple and can greatly improve the bit error rate performance in the high-speed environment.

The invention relates to a method for receiving a long scrambling code of a downstream cluster service in a time division duplex communication system, which comprises the steps as follows: a base station broadcasts and transmits system data information with the long scrambling code to a target user group in the cell; user equipment estimates channel impulse responses for training sequences in the cell and in the neighboring cells according to the received system data information to obtain the channel impulse responses corresponding to each cell; the power of the channel impulse responses of each cell is estimated to obtain the power of the channel impulse responses corresponding to each cell, and the power of the channel impulse responses is sorted to determine the cells with effective receptions; and the rake reception and interference elimination, demodulation and decoding process are carried out cell by cell to the cells with effective receptions so as to obtain expected user data. Based on the method, the invention also provides a receiver-transmitter unit for realizing the method. The invention effectively overcomes the multi-cell interference, so as to improve the transmission performance of the cluster mass-sending service and the cell capacity.