Combinations of correlation results are used to achieve detection of multiple coded signals at a receiver in a wireless communications system. The code applied to signals includes a lower rate code and a higher rate code. The lower rate code is a nested or tiered code such that it comprises at least two code sequences of the higher rate code. The received coded signal is correlated with the higher rate code using a single higher rate correlator to provide a higher rate code correlation result. The higher rate code correlation results are fed to two or more lower rate code correlators that combine multiple higher rate code-correlation results, each using a different lower rate code, to provide corresponding lower rate code correlation results. The presence of at least one coded signal or mutually exclusive coded signals can be determined from the lower rate code correlation results.

Disclosed are a beam scanning method and a base station, the method in which generated is a code book comprising a plurality of second precoders, defined by the weighted sums of a plurality of first precoders, and in which a plurality of synchronization signals, to which applied are second precoders that are selected from the code book and differ from each other, are transmitted to a terminal over a plurality of time intervals. The synchronization signals are used in synchronization, beam scanning and cell ID acquisition of the terminal, and each weighted sum applied to the plurality of first precoders indicates a beam ID used in the beam scanning.

Embodiments herein achieve a method and system for selecting non-coherent spreading sequences with binary alphabets {0, 1} with variable spreading factors. The method generates circular shift equivalent sets of spreading sequences by circularly shifting base sequences with elements {1, 0} and having at least one variable spreading factor. The method determines whether each spreading sequence in the circular shift equivalent set meets pre-defined spreading sequence criteria. The spreading sequence criteria comprise balanced criteria, a non- repetition criteria, non-circular criteria, and conjugate criteria. Furthermore, the method selects the spreading sequence from expansions of at least one spreading sequence from the circular shift equivalent sets in response to determining that the spreading sequences in the circular shift equivalent sets meets the pre-defined spreading sequence criteria.

A satellite communications system can use a spread-spectrum waveform and format, a synchronization scheme, and/or a power management algorithm. This approach can provide benefits such as allowing every terminal to communicate with every other terminal, link margin permitting. This gives the network a mesh topology although it can be configured in a star topology for highly asymmetric applications. A further understanding of the nature and the advantages of particular embodiments disclosed herein may be realized by reference of the remaining portions of the specification and the attached drawings.

Disclosed are a method for performing a random access and a terminal, the method comprising: acquiring information on a sequence set and information on a phase pattern vector set to be used during a random access step; selecting, from among a plurality of phase pattern vectors included in the phase pattern vector set, any one phase pattern vector corresponding to the repeating transmission frequency of an RACH signal; transmitting, to a base station, the generated RACH signal for a time period up to the repeating transmission frequency by using the selected phase pattern vector and any one sequence selected from among a plurality of sequences included in the sequence set; and receiving, from the base station, an RACH response signal indicating an estimated sequence and an estimated phase pattern vector.

The present invention is designed to optimize the uplink random access procedure even when coverage enhancement is applied to communication by user terminals, in which the bandwidth for use is limited to partial reduced bandwidths in a system bandwidth. A user terminal, in which the bandwidth to use is limited to a partial reduced bandwidth in a system bandwidth, has a receiving section that receives information related to repetitious transmission of a PRACH (Physical Random Access CHannel); and a transmission section that transmits the PRACH in repetitions in part or all of subframes based on the information related to repetitious transmission.

The present invention is designed to reduce the decrease of spectral efficiency even when repetitious transmission is applied to communication by user terminals, in which the band to use is limited to a partial narrow band in a system band. According to one aspect of the present invention, a user terminal, in which the band to use is limited to partial narrow bands in a system band, has a receiving section that receives information related to spreading codes, a generation section that generates uplink signals, and a transmission section that repeats transmitting uplink signals in a plurality of subframes, and the generation section applies a predetermined spreading code to an uplink signal that is transmitted in part or all of the plurality of subframes, based on the information related to spreading codes.

A single-channel Long Range (LoRa) receiver device. The device may comprise a communication component comprising a receiver spreading factor (SF), configured to accept LoRa signals. LoRa signals each comprise a transmitter SF. The communication component is only able to receive a LoRa signal if the receiver SF matches the transmitter SF. The device may change its receiver SF and detect LoRa signals. The device may then analyze a LoRa signal if the transmitter SF matches the receiver SF. The device may then synchronize the communication component to the LoRa signal, process the LoRa signal, and repeat changing, detecting, analyzing, and synchronizing until all LoRa signals in range are processed.

Provided is a method of blindly estimating WCDMA OVSF of a signal analyzer, which includes: (a) setting SF to 512 and an index thereof to 0; (b) calculating a power average value of a symbol obtained by despreading descrambled data with an OVSF code set by increasing the index from 0 by 1; (c) determining an OVSF code by which the power average value is equal to or greater than a power reference value as a used OVSF code candidate and determining an OVSF code by which the power average value is less than the power reference value as an unused OVSF code; (d) comparing a zero crossing rate of a symbol with a reference value to determine whether the OVSF code candidate is the used OVSF code; and (e) repeating (b) to (d) while reducing the SF half by half until the SF is equal to 4.

A cellular communication system comprising a plurality of geographically spaced base stations (2) each of which comprises an antenna arrangement (4, 6, 8) per base station sector, each of which antenna arrangements has an antenna element for generating an array of narrow beams (10, 12, 14) covering the sector. Timeslots are simultaneously transmitted over each of the beams so as to generate successive sets of simultaneously transmitted timeslots per sector. The timeslots are each split into multiple orthogonal codes, for example Walsh codes. The communication system additionally comprising a scheduling device (31) for allocating for successive sets of timeslots common overhead channels, including a common pilot channel, which are allocated to the same sub-set of codes of each timeslot in the set. For successive sets of timeslots different data traffic is allocated to the same sub-set of codes of each timeslot in the set. This effectively generates a sector wide antenna beam carrying the common overhead channels and a plurality of narrow beams each of which carry different data traffic. Inter-beam interference is addressed by the application of Adaptive Modulation and Coding and by an inter-beam handoff scheme. The handoff scheme ensures that when an end user equipment is located in a cusp region between adjacent beams the antenna arrangement simultaneously transmits data traffic to that mobile station on at least both of the adjacent beams.