A transmission method simultaneously transmitting a first modulated signal and a second modulated signal at a common frequency performs precoding on both signals using a fixed precoding matrix and regularly changes the phase of at least one of the signals, thereby improving received data signal quality for a reception device.

An optical transmission system includes an optical transmission apparatus and an optical reception apparatus. The optical transmission apparatus includes a conversion unit that converts multiple binary data sequences into data in a predetermined signal format; a coding unit that generates multiple pieces of coded data by performing predetermined coding on each of the multiple pieces of converted data; an optical signal generation unit that generates multiple optical signals by converting the multiple pieces of coded data into optical signals; and a mode multiplexer that converts the multiple optical signals into different modes, generates a mode-division multiplexed optical signal by mode-division multiplexing the optical signals, and transmits the generated mode-division multiplexed optical signal to the optical reception apparatus. The optical reception apparatus includes a mode demultiplexer that demultiplexes the mode-division multiplexed optical signal transmitted from the optical transmission apparatus into light in different modes; a photoelectric conversion unit that converts the light in the multiple different modes into electrical signals; an analog/digital conversion unit that converts the multiple electrical signals into coded data; and an MIMO equalization processing unit that performs MIMO equalization processing on the converted coded data.

A wireless audio system including a transmitter using multiple antenna diversity techniques for different signal types is provided. Multipath performance may be optimized, along with improved spectral efficiency of the system.

A transmission method simultaneously transmitting a first modulated signal and a second modulated signal at a common frequency performs precoding on both signals using a fixed precoding matrix and regularly changes the phase of at least one of the signals, thereby improving received data signal quality for a reception device.

A scheduling method for beamforming and a network entity are provided. In the method, a future location is predicted according to one or more past locations of a user equipment (UE). A precoder is determined according to the future location. A direction of a beam of a base station is determined according to the precoder. The past locations are locations of the UE at one or more past time points, and the future location is a location of the UE at a future time point. The precoder reflects a downlink channel state at the future time point. Accordingly, the communication quality can be improved.

A method for selecting a cyclic shift diversity sequence, and a related apparatus are disclosed. The method includes: sending a frame by using a cyclic shift diversity (CSD) sequence, comprising: generating a frame, wherein the frame comprises a first data subframe conforming to a first communication mechanism and a third data subframe conforming to the first communication mechanism; sending the frame, wherein the first data subframe and the third data subframe are sent by using a cyclic shift diversity sequence. Under an EHT standard, a preferred cyclic shift diversity sequence can be obtained through selection from massive combinations of CSD values. Work efficiency is improved, and an operation burden is reduced.

An audio streaming system including an audio streamer connected to an audio source, and at least one ear worn device. The audio streamer includes a first antenna with a first polarization, a second antenna with a second polarization, and a radio configured for transmitting a first audio stream signal (30) from the first antenna and a second audio stream signal (31) from the second antenna. The first audio stream signal (30) and the second audio stream signal (31) carry the same audio information and are shifted in time. At least one ear worn device is configured to receive the first audio stream signal (30) and the second audio stream signal (31), compare the signal strength of the first audio stream signal (30) and the second audio stream signal (31), and select either the first audio stream signal (30) and the second audio stream signal (31) as input for audio reception.

A rate-adaptive method of communicating over a multipath wireless communication system uses multiple links such that each end of a link uses multiple transmit and receive antennas. A number of independent streams that are to be transmitted for each link is determined based on an overall system performance measure. In addition, the system may also jointly determine the best modulation, coding, power control, and frequency assignment for each link, based on an overall system performance measure. In OFDM systems, the number of independent streams, as well as the modulation, coding, and power control, may be determined on a tone-by-tone basis based on an overall system performance measure.

A transmission method simultaneously transmitting a first modulated signal and a second modulated signal at a common frequency performs precoding on both signals using a fixed precoding matrix and regularly changes the phase of at least one of the signals, thereby improving received data signal quality for a reception device.

A system for providing sound to at least one user, having at least one audio signal source for providing audio signals; a transmission unit with a digital transmitter for wirelessly transmitting the audio signals as data packets; at least one receiver unit with at least one digital receiver for reception of the audio signals from the transmission unit; a mechanism for stimulating the hearing of the user(s) according to audio signals supplied from the receiver unit. The transmission unit transmits each data packet in a separate slot of a TDMA frame at a different frequency in a frequency hopping sequence, in at least some of the slots, the audio signals are transmitted as audio data packets, the same audio packet being transmitted at least twice in the same TDMA frame without expecting acknowledgement, and the TDMA frames being structured for unidirectional broadcast transmission of the audio data packets.