560results about How to "Improve reception quality" patented technology

Provided is a digital multimedia broadcasting (DMB) system that can provide a multimedia data broadcasting service having an excellent reception quality, a method thereof, and a computer-readable recording medium for recording a program that implements the method. The DMB system includes an encoding unit for encoding an inputted audio / video signal; a synchronizing unit for synchronizing media stream, additional data, interactive service objectifying data that are outputted from the encoding unit; a multiplexing unit for multiplexing the media stream outputted from the synchronizing unit; an error correction encoding unit for performing additional error correction encoding on the media stream outputted from the multiplexing unit; an interleaving unit for removing temporal correlation between adjacent byte units within a data stream outputted from the error correction encoding unit; and a transmitting unit for transmitting a DMB media stream outputted from the interleaving unit to the conventional DAB system and other digital broadcasting systems.

A communication device for transmitting and / or receiving signals by using a communication antenna includes signal characteristic information detection means for detecting information regarding signal characteristics of a calibration signal which are contained in a signal received by the communication antenna, calibration means for calibrating a communication antenna chain based on the detected signal characteristic information, and cancellation signal generating means for generating a cancellation signal corresponding to a calibration signal contained in the signal received by the communication antenna based on the calibration signal. The device also includes signal cancellation-by-subtraction means for subtracting the generated cancellation signal from the signal received by the communication antenna, and receive signal processing means for processing the received signal that is diminished by the cancellation signal.

Disclosed is a high frequency apparatus which eliminates an influence of interfering signals. An interference-cut filter (24) for eliminating interfering signals is disposed between an input terminal (22) and a mixer (27). The interference-cut filter (24) is so controlled that it effectively demonstrates the function while the interfering signals are transmitted. Control of the interference-cut filter (24) is made by a switch (23), which is controlled by a selector switch controller (39), and the switch controller (39) is controlled responsive to an error correction counter (38) and a radio wave transmitted from a cellular telephone (40). This structure eliminates interference attributable to communication signals transmitted by the cellular telephone (40) and undesirable signals entering from the outside. The invention can thus realize high quality reception.

A wireless communication, in which mobile and base stations setup uplink and downlink channels, and the mobile station transmits data flows. The base station interrupts transmission via the downlink setup with the mobile station in the predetermined transmission interruption time interval. The mobile station determines, in response to the data flow, packet transmission in a first transmission time interval for the predetermined time interval determined from the transmission interruption time interval or re-transmission of the packets transmitted in the first transmission time interval. The mobile station transmits packets in response to the determination. The base station transmits an arrival confirmation signal for the transmitted packets. The mobile station performs re-transmission in response to the arrival confirmation signal or to the determination.

An open-loop power controller of a transmission power control apparatus investigates whether a dedicated control channel DCCH and a synchronization channel SCH overlap. If the channels overlap, the open-loop power controller suspends ordinary open-loop power control processing, increases a target SIR by a satisfactory level and indicates this to a closed-loop power controller. The closed-loop power controller maintains the indicated target SIR and executes closed-loop transmission power control processing based upon the target SIR. The open-loop power controller resumes ordinary open-loop transmission power control processing after DCCH reception ends.

A mobile station includes a control unit configured to change at least one parameter for a retransmission packet from that of a transmission packet, where the at least one parameter is selected from a data modulation scheme; a channel coding rate; a puncturing pattern; a spreading factor; a frequency bandwidth; a frequency allocation position; and transmission power. A base station includes a retransmission format determining unit configured to determine a pattern used for changing at least one parameter for a retransmission packet from that of a transmission packet to determine a format for the retransmission packet, where the at least one parameter is selected from a data modulation scheme; a channel coding rate; a puncturing pattern; a spreading factor; a frequency bandwidth; a frequency allocation position; and transmission power; and a control signal generating unit configured to generate a control signal based on the format for the retransmission packet determined by the retransmission format determining unit.

A transmitting apparatus which transmits a transmit symbol in orthogonal-frequency division multiplexing (OFDM) is disclosed. The transmitting apparatus includes a unit which provides a unicast channel; a unit which provides a multimedia broadcast multicast service (MBMS) channel; a unit which provides a specific pilot channel which is specific to a specified cell; a unit which provides one or more common pilot channels common to a plurality of cells; and a multiplexing unit which multiplexes the unicast channel, the MBMS channel, the specific pilot channel, and the one or more common pilot channels, and creates the transmit symbol, wherein the multiplexing unit time-division multiplexes, in the same frequency band, a unicast frame which includes the unicast channel, and an MBMS frame which includes the MBMS channel, and wherein an insertion density of the common pilot channel included in the MBMS frame is larger than an insertion density of the specific pilot channel included in the unicast frame.

A DTV transmitter includes a pre-processor pre-processing supplemental data, a multiplexer multiplexing pre-processed data with main data, and a byte-symbol converter converting each data byte of the multiplexed data into a symbol. It further includes a symbol processor processing each supplemental data symbol outputted from the byte-symbol converter. It encodes one of upper and lower bits of each supplemental data symbol into first and second data bits, post-decodes the first data bit, and outputs the post-decoded data bit and the second data bit as a symbol. The DTV transmitter further includes a symbol-byte converter converting each symbol outputted from the symbol processor into a data byte.

A method of transmitting a grant-free uplink data channel (physical uplink shared channel (PUSCH)) (GF-PUSCH), performed in a terminal, includes determining a resource (GF-PUSCH resource) for transmission of the GF-PUSCH and an identifier (DM-RS ID) of a demodulation reference signal (DM-RS) included in the GF-PUSCH; when an uplink traffic arrives, encoding the uplink traffic into a transport block (TB); generating the DM-RS based on the DM-RS ID, and transmitting the GF-PUSCH including the TB and the DM-RS to a base station through the GF-PUSCH resource; and receiving, from the base station, a group hybrid automatic repeat request acknowledgement (HARQ-ACK) information in which ACK or negative acknowledgement (ACK / NACK) information for the GF-PUSCH of the terminal and ACK / NACK information for at least one GF-PUSCH of at least one other terminal are multiplexed, through a downlink control information (DCI).

A pre-processor pre-processes enhanced data packets by coding the enhanced data packets for forward error correction (FEC) and expanding the FEC-coded data packets. A data formatter adds first null data into first place holders within each pre-processed enhanced data packet. A first multiplexer multiplexes the main data packets with the enhanced data packets having the first null data. A holder inserter inserts second null data into second place holders within an enhanced data packet outputted from the first multiplexer. A data interleaver replaces the second null data with parity data. A data generator generates at least one known data sequence. A symbol processor replaces the first null data included in an output of the data interleaver with the known data sequence(s). A non-systematic RS encoder generates the parity data by performing non-systematic RS-coding on an output of the symbol processor, and provides the parity data to the data interleaver.

A wireless communication apparatus includes a plurality of antennas that transmit modulation signals. A controller controls a control signal of the modulation signals based on an eigenvalue corresponding to a channel matrix generated using the modulation signals received by a communicating party.

A DTV transmitting system includes an encoder, a randomizer, a block processor, a group formatter, a deinterleaver, and a packet formatter. The encoder codes enhanced data for error correction, permutes the coded data, and further codes the permuted data for error detection. The randomizer randomizes the coded enhanced data, and the block processor codes the randomized data at an effective coding rate of 1 / H. The group formatter forms a group of enhanced data having data regions, and inserts the coded enhanced data into at least one of the data regions. The deinterleaver deinterleaves the group of enhanced data, and the packet formatter formats the deinterleaved data into corresponding data bytes.

Modulation scheme control section 155 determines a modulation scheme of a transmission signal based on the reception electric field strength of the entire system estimated in an apparatus of a communicating party and a value of the mean effective reception electric field strength, and outputs a control signal for instructing a determined modulation scheme to S / P sections 102-1 and 102-2. S / P sections 102-1 and 102-2 receive the transmission digital signal, perform the serial / parallel transform processing, further perform the adaptive modulation processing according to the instruction from modulation scheme control section 155. It is thereby possible to control a parameter of the modulation scheme or the like in consideration of relative relationships between channels, and it is thus possible to improve the reception quality.