Systems and methods are disclosed for detecting node outages in a mesh network. A tracking node in the mesh network detects a set of signals originating from a tracked node in the mesh network. The set of signals includes beacons and communication messages transmitted by the tracked node. The tracking node determines that a threshold number of the alive beacon intervals have passed since receiving a most recent signal from the tracked node. The tracking node then outputs a ping to the tracked node requesting a response to the ping. When the response to the ping is not received from the tracked node, the tracking node transmits an outage alarm message to a next topologically higher layer of the mesh network, the outage alarm message comprising an identification of the tracked node.

A system and method of DFT-S-OFDM modulation is provided that uses a set of frequency domain patterns. For a given transmitter, for a set of DFT-S-OFDM symbols, the frequency domain pattern changes according to a time domain hopping pattern. Advantageously, the time domain hopping patterns are defined to allow only a certain amount of overlap, for example for only one DFT-S-OFDM symbol, between any two time domain hopping patterns. This functions to reduce the effect of a collision, when two transmitters use the same frequency pattern, they will do so only for part of the overall transmission. Optionally, frequency domain spectral spreading is used in the transmitter. This can further reduce the PAPR. In the receiver, successive interference cancellation may be employed to reduce the effect of colliding transmissions.

Systems and methods are disclosed for detecting node outages in a mesh network. A tracking node in the mesh network detects a set of signals originating from a tracked node in the mesh network. The set of signals includes beacons or communication messages transmitted by the tracked node. The tracking node determines that a threshold number of the beacon intervals have passed since receiving the most recent signal from the tracked node. The tracking node performs outage validation based on data received from another node in the mesh network and updates the status of the tracked node. Based on the updated status, the tracking node outputs a ping to the tracked node requesting a response to the ping. When the response to the ping is not received from the tracked node, the tracking node transmits an outage alarm message to a next topologically higher layer of the mesh network.

A spread-spectrum transmitter is disclosed. The transmitter includes a modulator configured to produce an intermediate frequency signal, a frequency shifter configured to shift the intermediate frequency factor by a first factor, and a local oscillator (LO) configured to generate a LO signal. The transmitter further includes a ramp signal generator configured to determine the value of the first factor and a second factor, is configured to transmit the value of the factor to the frequency shifter, is configured to transmit the value of the second factor to the LO, where the frequency of the intermediate frequency signal shifted by the first factor is shifted synchronously with the frequency of the LO signal shifted by the second factor. The transmitter includes a mixer configured to mix the shifted intermediate frequency with the shifted LO signal that has been shifted by the second factor, producing a spread leaked LO signal.

Disclosed is an ultra-wideband (UWB) system and, more particularly, a UWB system using UWB ranging factor definition. The UWB system using the UWB ranging factor definition includes a memory in which a UWB ranging factor definition program is embedded and a processor which executes the program, wherein the program predefines UWB ranging factors to define a scrambled timestamp sequence (STS) index, an encryption key, and a nonce.

Embodiments provide a method for generating a hopping pattern for transmitting a plurality of sub-data packets in a communication system. The method has a step of deriving a hopping pattern from a binary sequence, wherein an autocorrelation function of the binary sequence has autocorrelation side maximums with a predetermined maximum value. The method further has a step of determining a maximum sub-data packet length for the plurality of sub-data packets in dependence on a total emission duration of the plurality of sub-data packets indicated by the hopping pattern, and a minimum value of a difference sequence of a sorted difference number series derived from the binary sequence.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station, a transmission part (TP) hopping configuration that indicates one or more TPs and a TP hopping pattern associated with one or more hops between the one or more TPs. The UE may communicate, with the base station, using a TP of the one or more TPs based at least in part on the TP hopping configuration. Numerous other aspects are described.

Embodiments of the present invention disclose a broadcast information sending method, a broadcast information receiving method, a device, and a system, relate to the communications field, and are used to reduce system overheads, and improve coverage performance. The method provided by the embodiments of the present invention includes: sending, by a network device on a physical broadcast channel PBCH, PBCH information to user equipment UE, and sending, by the network device, the PBCH information in a specific radio frame in each period T of the PBCH, where the PBCH information only includes information about a system frame number SFN, and the period T is greater than one radio frame.

Embodiments provide a transmission method for wireless transmission of data within a communication system. The method includes a step of transmitting the data in a manner that is time-synchronized with a reference signal while using a frequency hopping pattern and/or time hopping pattern.

Disclosed are a D2D communication method and device on the basis of a hopping sequence. A D2D communication method on the basis of a hopping sequence may comprise the steps of: obtaining information on a reference hopping sequence by a terminal wherein the reference hopping sequence is a current hopping sequence of a target terminal which will perform first D2D communication on the basis of a first link with the terminal; determining a final hopping sequence for performing the first D2D communication by the terminal on the basis of whether the terminal is an initial access terminal or a multi-access terminal and whether the current hopping sequence of the terminal is the same as at least one of communicable hopping sequences corresponding to a reference sequence and the reference hopping sequence; and performing the first D2D communication by the terminal on the basis of the final hopping sequence.