An apparatus for simultaneous transmit and receive is provided. The apparatus is capable of rejecting or passing transmitter and receiver signals. The apparatus includes: a transmitter; an antenna (e.g., a shared antenna); a receiver including switches controllable by time varying signals; and a quadrature coupler including first, second, third, and fourth ports, wherein the first port is coupled to the transmitter, wherein the second port is coupled to the antenna, and wherein the third and fourth ports are coupled to the receiver.

A communications node operable to communicate with another communications node over a communications channel having a plurality of frequency resources, the communications node includes data defining a division of the communications channel into a plurality of contiguous sub-bands each having N frequency resources, wherein each frequency resource in a sub-band has a corresponding frequency resource in each of the other sub-bands, data defining an initial allocation of the frequency resources, a resource determination module operable to apply a frequency shift to the initially allocated frequency resources in accordance with a frequency hopping sequence to determine frequency resources to use for communicating information with the other communications node, wherein the frequency shift applied moves the initially allocated frequency resources to corresponding frequency resources in another sub-band, a transceiver for communicating information with the other communications node using the determined frequency resource.

A wideband carrier (e.g., LTE carrier) is shifted up or down in frequency, within an allocated frequency band, by an integer multiple of the channel raster spacing (e.g., 100 KHz). This reduces the size of the guard band on one side of the carrier, and expands the guard band on the other side. A narrowband carrier (e.g., NB-IoT carrier) is then deployed within the expanded guard band, at or near a frequency such that the transmission is orthogonal to the wideband carrier transmissions, such as by using a shared N frequency grid spacing (e.g. at 100 KHz spacing, and using 15 KHz subcarriers). The narrowband carrier thus maintains orthogonality with the wideband carrier, but has room within the expanded guard band to both transmit on a frequency close to the frequency grid spacing, and to boost transmit power (e.g., by 6 dB), while remaining within the spectral mask. The shifted wideband carrier is transparent to wideband UEs, as the frequency shift is an integer multiple of the channel raster spacing.

A communications node operable to communicate with another communications node over a communications channel having a plurality of frequency resources, the communications node includes data defining a division of the communications channel into a plurality of contiguous sub-bands each having N frequency resources, wherein each frequency resource in a sub-band has a corresponding frequency resource in each of the other sub-bands, data defining an initial allocation of the frequency resources, a resource determination module operable to apply a frequency shift to the initially allocated frequency resources in accordance with a frequency hopping sequence to determine frequency resources to use for communicating information with the other communications node, wherein the frequency shift applied moves the initially allocated frequency resources to corresponding frequency resources in another sub-band, a transceiver for communicating information with the other communications node using the determined frequency resource.

According to aspects of the disclosure, a method is disclosed comprising: detecting a first hop to a first frequency in a hopping sequence, the first hop being performed by a transmitter in accordance with the hopping sequence; identifying a weighting vector that corresponds to a second frequency in the hopping sequence; obtaining an equalizer vector for the second frequency based on the weighting vector and an equalizer matrix, the equalizer matrix including a plurality of equalizer vectors, each equalizer vector corresponding to a different frequency in the hopping sequence; detecting a second hop from the first frequency to the second frequency, the second hop being performed by the transmitter in accordance with the hopping sequence; receiving a signal that is transmitted by the transmitter at the second frequency; and equalizing the signal by using the equalizer vector for the second frequency.

There is provided a wireless device capable of supporting both of TDD and FDD wireless communications with a simple configuration. The wireless device includes a transmitter that transmits a signal of a first frequency; a DPD receiver that receives signals of the first frequency; a receiver that receives signals of a second frequency; a duplexer having a first filter having passband characteristics in the first frequency band and a second filter having passband characteristics in the second frequency band; and a circulator that splits the signal from the transmitter to output the split signals to the duplexer and the DPD receiver, and outputs a reception signal from the duplexer to the DPD receiver. The duplexer is connected to the circulator on the first filter side and to the receiver on the second filter side, and uses the DPD receiver for FDD and TDD transmission feedback and for TDD reception.

A communications node operable to communicate with another communications node over a communications channel having a plurality of frequency resources, the communications node includes data defining a division of the communications channel into a plurality of contiguous sub-bands each having N frequency resources, wherein each frequency resource in a sub-band has a corresponding frequency resource in each of the other sub-bands, data defining an initial allocation of the frequency resources, a resource determination module operable to apply a frequency shift to the initially allocated frequency resources in accordance with a frequency hopping sequence to determine frequency resources to use for communicating information with the other communications node, wherein the frequency shift applied moves the initially allocated frequency resources to corresponding frequency resources in another sub-band, a transceiver for communicating information with the other communications node using the determined frequency resource.

Methods and apparatus for multiple user uplink are provided. In one aspect, a method for wireless communication is provided. The method includes receiving a trigger frame from an access point, the trigger frame being transmitted to two or more stations and indicating an uplink transmission opportunity. The trigger frame further includes a request for the two or more stations to concurrently transmit uplink data at a specific time. The method includes transmitting uplink data at the specific time to the access point concurrently with another of the two or more stations transmitting uplink data to the access point.

Devices, systems and methods for operating a rear-facing perception system for vehicles are described. An exemplary rear-facing perception system contains two corner units and a center unit, with each of the two corner units and the center unit including a camera module and a dual-band transceiver. A method for operating the rear-facing perception system includes pairing with a control unit by communicating, using the dual-band transceiver, over at least a first frequency band, transmitting a first trigger signal to the two corner units over a second frequency band non-overlapping with the first frequency band, and switching to an active mode. In an example, the first trigger signal causes the two corner units to switch to the active mode, which includes orienting the camera modules on the center unit and the two corner units to provide an unobstructed view of an area around a rear of the vehicle.

Embodiments of the present disclosure disclose a signal transmission apparatus and non-transitory computer-readable storage medium, and relate to the field of communications technologies. The apparatus comprises a memory storing program instructions and a processor coupled to the memory, wherein the program instructions, when executed by the processor, cause the apparatus to obtain configuration information for use to transmit a signal of a second carrier in coverage space of a first carrier, a spectrum occupied by the first carrier and a spectrum occupied by the second carrier overlap, and a subcarrier of the first carrier and a subcarrier of the second carrier are orthogonal; and transmit the signal of the second carrier according to the configuration information.