A transmission device includes: a reference sequence obtaining unit that obtains a reference sequence having a symbol sequence length equal to or smaller than a modulation order in a modulation method used for data transmission, the reference sequence having a constant amplitude in a time domain and a frequency domain; and a multiplexing unit that transmits a signal including the reference sequence.

Filter characteristics of a first filter are improved while suppressing degradation in filter characteristics of a second filter. A multiplexer includes a first terminal, a second terminal, a first filter, a second filter, and a capacitive element. The first filter and the second filter are connected to an antenna via the first terminal. The first filter includes a plurality of series arm resonators, a plurality of parallel arm resonators, and an inductor. The inductor is provided between the parallel arm resonator and ground. A first end portion of the capacitive element is connected to a first path at a position in between the series arm resonator that is the closest to the first terminal and the second terminal. A second end portion of the capacitive element is connected between the parallel arm resonator and the inductor.

Filter characteristics of a first filter are improved while suppressing degradation in filter characteristics of a second filter. A multiplexer includes a first terminal, a second terminal, a first filter, a second filter, and a capacitive element. The first filter and the second filter are connected to an antenna via the first terminal. The first filter includes a plurality of series arm resonators, a plurality of parallel arm resonators, and an inductor. The inductor is provided between the parallel arm resonator and ground. A first end portion of the capacitive element is connected to a first path at a position in between the series arm resonator that is the closest to the first terminal and the second terminal. A second end portion of the capacitive element is connected between the parallel arm resonator and the inductor.

A method of auto-detection of WLAN packets includes selecting a first Golay sequence from a first pair of Golay complementary sequences associated with first packet type, each Golay sequence of the first pair of Golay complementary sequences being zero correlation zone (ZCZ) sequences with each Golay sequence of a second pair of Golay complementary sequences associated with a second packet type, and transmitting a wireless packet carrying a short training field (STF) that includes one or more instances of the first Golay sequence.

An information transmission method and a device are provided. The information transmission method includes: receiving, by a terminal device, downlink control information sent by a network device, the downlink control information including a resource allocation field, the resource allocation field being used to indicate allocated resource block(s) or a subcarrier resource. The method further includes determining, by the terminal device, an allocated resource based on the downlink control information, and sending information on the allocated resource. According to the method and the device provided in embodiments of this application, a coverage capability of a network is improved, and the method and the device may be applied to the internet of things, for example, MTC, IoT, LTE-M, and M2M.

An apparatus, method and wireless device for fast scanning of a wireless communications medium are disclosed. According to one aspect, a method includes tuning a transceiver of the wireless node to a first frequency. The method further includes computing a first difference frequency, the first difference frequency being a difference between the first frequency and a second frequency. The method further includes generating a first control signal to configure a first backscattering device to switch between at least two states at a switching frequency equal to the first difference frequency.

Methods, systems, and devices for contention-based transmissions using differential coding techniques in mobile communication technology are described. An exemplary method for wireless communication includes transmitting, by a wireless device, a payload including a first portion that is modulated using a differential coding technique and a second portion that is modulated using an amplitude-shift keying (ASK) or phase-shift keying (PSK) modulation, and where the payload includes an identity of the wireless device and at least one of a user plane data or a control plane data.

Methods, systems, and devices for contention-based transmissions using differential coding techniques in mobile communication technology are described. An exemplary method for wireless communication includes transmitting, by a wireless device, a payload including a first portion that is modulated using a differential coding technique and a second portion that is modulated using an amplitude-shift keying (ASK) or phase-shift keying (PSK) modulation, and where the payload includes an identity of the wireless device and at least one of a user plane data or a control plane data.

A signal modulation apparatus, a memory storage apparatus, and a signal modulation method are disclosed. The signal modulation apparatus includes an observation circuit, a signal modulation circuit, and a phase control circuit. The signal modulation circuit is configured to generate a second signal according to a first signal and a reference clock signal. A frequency of the first signal is different from a frequency of the second signal. The phase control circuit is configured to obtain an observation information via the observation circuit. The observation information reflects a process variation of at least one electronic component in the signal modulation apparatus. The phase control circuit is further configured to control an offset between the first signal and the reference clock signal according to the observation information.

Methods and systems are described for obtaining a set of carrier-modulated symbols of a carrier-modulated codeword, each carrier-modulated symbol received via a respective wire of a plurality of wires of a multi-wire bus, applying each carrier-modulated symbol of the set of carrier-modulated symbols to a corresponding transistor of a set of transistors, the set of transistors further connected to a pair of output nodes according to a sub-channel vector of a plurality of mutually orthogonal sub-channel vectors, recovering a demodulation signal from the carrier-modulated symbols, and generating a demodulated sub-channel data output as a differential voltage on the pair of output nodes based on a linear combination of the set of carrier-modulated symbols by controlling conductivity of the set of transistors according to the demodulation signal.