175 results about "Frequency division duplexing" patented technology

Integrating dual antennae into a single rigid assembly guarantees parallel alignment between the antennae and provides higher isolation with lower insertion loss than duplexing methods can achieve through a single antenna. The resulting higher performance at lower cost can benefit two-way communication systems using time division duplexing, frequency division duplexing, or polarization division duplexing; or combinations of these methods.

The invention discloses methods and device for transmitting and receiving ACK/NACK (acknowledgement/negative acknowledgement). The method for transmitting the ACK/NACK comprises: when a PUSCH (physical uplink shared channel) used for transmitting uplink control information and determined by user equipment (UE) is a PUSCH which has no corresponding PDCCH (physical downlink control channel), or a PUSCH under the uplink configuration and downlink configuration 0 in a TDD (time division duplexing) system, or a PUSCH in an FDD (frequency division duplexing) system, if the UE does not receive the PDSCH in a downlink subframe which performs ACK/NACK feedback in an uplink subframe which sends the PUSCH correspondingly, or if the UE instructs the PDCCH released by downlink SPS (semi-persistent scheduling) resources, the UE determines the ACK/NACK feedback information transmitted on the PUSCH; the UE determines the resources for transmitting the ACK/NACK feedback information on the PUSCH; and the UE transmits the ACK/NACK feedback information on the determined resources for transmitting the ACK/NACK feedback information on the PUSCH. According to the invention, the inconformity of understanding on whether the ACK/NACK is transmitted on the PUSCH by a base station and the UE caused by the UE downlink data loss can be avoided, and the transmission reliability of the downlink data and ACK/NACK feedback information can be improved.

A method for allocating an Acknowledgement/Negative Acknowledgement (ACK/NACK) channel by a Base Station (BS) in a Frequency Division Duplexing (FDD) system is provided. The method includes allocating downlink resources in one or more cells to a User Equipment (UE), transmitting, Physical Downlink Control Channel (PDCCH) information and downlink data using the downlink resources, allocating at least four ACK/NACK channels to the UE, receiving ACK/NACK information for the PDCCH information and the downlink data fed back by using two antennas from the UE, and performing re-transmission or transmitting new data according to the ACK/NACK information, wherein at least two of the at least four ACK/NACK channels are the same as at least two ACK/NACK channels allocated by the BS in a mode not using a Spatial Orthogonal Resource Transmit Diversity (SORTD) scheme, and the at least two of the at least four ACK/NACK channels are allocated to different antennas.

A method, apparatus, and computer-readable medium for performing asymmetric frequency division duplexing (FDD) are provided. The method includes allocating a first bandwidth for an uplink portion of an FDD data transmission; and allocating a second bandwidth for a downlink portion of the FDD data transmission; wherein the first bandwidth and the second bandwidth have different sizes.

There is provided to an RF calibration apparatus and method for a multi-antenna mobile communication system, which calibrates a phase error and gain error of an RF path by calculating the minimum value of a sum of an initialized reference signal and a comparison signal by a simple operation and controlling the phase value of a phase converter and the gain of a variable amplifier on the RF path, in calibrating the RF path of a multi-antenna mobile communication system of a TDD (Time Division Duplexing) type or FDD (Frequency Division Duplexing) type.

The embodiment of the invention provides a dual-connection communication structure and an uplink method thereof, which relate to the field of communication and can satisfy the SAR (Specific AbsorptionRate) limit requirement while guaranteeing the uplink coverage. The method includes the following steps: a user terminal sends a scheduling request containing the maximum uplink transmission power toa TDD (Time Division Duplexing) base station and an FDD (Frequency Division Duplexing) base station; when the maximum uplink transmission power is determined to be greater than a preset power, the TDD base station sends a first uplink duty cycle to the FDD base station; the FDD base station sets a second uplink duty cycle according to the first uplink duty cycle to enable the average uplink transmission power of each wireless frame length in the communication connection between the two terminal and a target base station to be less than or equal to the preset power; and the TDD base station and the FDD base station respectively send a first scheduling consent permission including a first uplink slot and a second scheduling consent permission containing a second uplink slot generated thereby to the user terminal so that the user terminal can transmit uplink information to the target base station in the first uplink slot and the second uplink slot.

A method and device for realizing frequency spectrum coordination between Time Division Duplexing (TDD) system and Frequency Division Duplexing (FDD) system, which include that: obtaining resource assignment result and user information to be scheduled of the TDD system and the FDD system (100), accounting the needed uplink bandwidth of the TDD system and the useable uplink bandwidth of the FDD system (101); based on the accounted result, realizing that the TDD system transmits upwardly on the uplink resource of the FDD system (102). By the method of the present invention, when the uplink bandwidth of the FDD system is residual and the uplink bandwidth of the TDD system is lacking, the TDD system can transmit upwardly on the uplink frequency band of the FDD system, the flexible assignment of the frequency spectrum between the TDD system and the FDD system is realized, the utilization ratio of the frequency spectrum and the throughput of the system are improved.

This invention relates to a quick hop-expansion communication method based on OFDM, in which, an transmission end generates frequency expansion sequence, sub-carrier distribution signals and FH sequences according to user request, carries out direct sequence frequency expansion or code process then to modulate symbols then distributes the modulated signals to the sub-carriers of communication signals of users according to the sub-carrier distribution signals to be added with circulation prefix for D/A conversion then modulates the received analog signal to the carrier frequency generated according to the FH sequence, the receiving end receives signals then carries out de-FH, A/D conversion and removing the circulation prefix and de-modulates the modulation signals on the sub-carrier of the user communication signals to be output in series to get the user data after the symbol is de-modulated, de-coding or de-FH.

Techniques for extending coverage of a wireless communication network (e.g., a cellular network) to indoor and other locations are described. A wireless device may communicate with a base station in awireless network via downlink and uplink frequency channels in a licensed frequency band using frequency division duplexing (FDD). The wireless device may communicate with a piconet base station (PBS) in a pico network (piconet) via the uplink frequency channel using time division duplexing (TDD). The PBS may communicate with the wireless device on the uplink frequency channel and may exchange data with the wireless network via a wireline communication link. The PBS may forward data received from the wireless device to the wireless network and may also forward data received from the wirelessnetwork for the wireless device to the wireless device. The PBS may receive paging messages from the wireless network for the wireless device and may forward the paging messages to the wireless device.

The invention discloses a downlink channel estimation method for use in an FDD (Frequency Division Duplexing) large-scale MIMO (Multiple-Input Multiple-Output) system. The method comprises the following steps: constructing an uplink pilot signal receiving model of the FDD large-scale MIMO system; performing compressed sensing channel estimation on an uplink space channel; acquiring a support set of the uplink space channel according to an estimated value of the uplink space channel, and estimating a support set of a downlink space channel according to the support set of the uplink space channel; constructing a downlink pilot signal receiving model of the FDD large-scale MIMO system; and performing downlink compressed sensing channel estimation based on estimation support set information ofthe downlink space channel. According to the method disclosed by the invention, a sparse support set of the downlink space channel is estimated according to an estimation result of the uplink space channel by means of the spatial correlation between the uplink channel and the downlink channel, thereby improving the performance of downlink channel estimation.

The invention discloses mode converting method, device and system in a FDD (Frequency Division Duplex) scene, which relates to the field of wireless communication and can solve the problem that a MS can not realize mode conversion. The method comprises the following steps of: receiving a request message of mode conversion, which is transmitted by an Access Station, wherein the request message requests the MS to convert into an H-FDD (Half-Frequency Division Duplex) mode from an F-FDD (Full-Frequency Division Duplex) mode or convert into the F-FDD mode from the H-FDD mode; and converting to the appointed mode in the request message. The mode converting method in the FDD scene of the other embodiment comprises the following steps of: transmitting the request message of mode conversion to the Access Station, wherein the request message requests the MS to convert into the H-FDD mode from the F-FDD mode or convert into the F-FDD mode from the H-FDD mode; receiving a feedback message that the Access Station agrees to convert and then converting to the appointed mode in the request message. The invention is suitable for the mode conversion in the FDD scene.

A physical-layer device includes a first sublayer to receive a first continuous bitstream from a media-independent interface and to provide a second continuous bitstream to the media-independent interface. The physical-layer device also includes a second sublayer to transmit first signals corresponding to the first continuous bitstream and to receive second signals corresponding to the second continuous bitstream. The second sublayer is to transmit the first signals and receive the second signals using time-division duplexing in a first mode of operation and using frequency-division duplexing in a second mode of operation.

The invention discloses a frequency division duplex downlink transmission method based on Bayesian neural network channel prediction. The method comprises the following steps: (1) storing a pluralityof pieces of past channel state information as training data by a base station, and training a Bayesian neural network with initialized parameters by utilizing the training data; (2) in the downlink transmission process, the base station predicting the channel state information of the next transmission time slot by using the trained Bayesian neural network; at the next transmission time slot, thebase station using the predicted channel state information for precoding and transmission of data to be sent in an uplink feedback waiting stage; (3) the base station obtaining estimated channel stateinformation through the fed back information, and sending downlink data in a transmission stage by utilizing the estimated channel state information; and meanwhile, the base station continuously predicting the channel state information of the next transmission time slot through the Bayesian neural network. According to the invention, the downlink transmission rate of the large-scale MIMO system can be further improved.

The invention discloses an ACK/NACK (Acknowledgement/Negative Acknowledgement) feedback method and system for FDD (Frequency Division Duplexing) downlink multi-subframe scheduling. The core concept of the ACK/NACK feedback method and system is that eNB specially configures PUCCH (Physical Uplink Control Channel) resources for ACK/NACK feedback during downlink multi-subframe scheduling in an uplink frequency spectrum of each subframe for UE (User Equipment). One solution is that the PUCCH resources are configured for each piece of UE in the uplink frequency spectrum of the subframe; another solution is that a plurality of or multiple groups of shared PUCCH resources are configured for multiple pieces of UE in the uplink frequency spectrum of the subframe, and then a PUCCH resource indication domain is defined in a PDCCH (Physical Downlink Control Channel) of each downlink subframe for indicating one or one group of PUCCH resources, so that the ACK/NACK during the downlink multi-subframe scheduling is fed back on the specially configured PUCCH resources. Therefore, the conflict of the PUCCH resources during the ACK/NACK feedback during the multi-subframe scheduling in FDD can be avoided.