The present disclosure provides a base station capable of improving the frequency utilization efficiency in uplink. In the base station (100), a receiver (112) receives a transmission signal to be repeatedly transmitted over a plurality of allocation units, and a reception signal processor (114) demodulates the transmission signal based on a combination of non-orthogonal multiple access where signals of a plurality of terminals are not orthogonal with each other, and orthogonal multiple access where signals of a plurality of terminals are orthogonal with each other.

User equipment (UE) applies a first code division multiplex access (CDMA) code to a baseband signal to generate a first signal, and a second CDMA code to the baseband signal to generate a second signal. The UE then transmits the first signal to a receiving device via a first antenna, and the second signal to the receiving device via a second antenna. The receiving device receives the first and second signals as a combined signal at an antenna, and extracts the first signal from the combined signal using the first CDMA code, and extracts the second signal from the combined signal using the second CDMA code. The CDMA codes may be real-valued or complex-valued. In some embodiments, the UE may separate the baseband signals into first and second portions, and transmit the first portion as part of the first signal and the second portion as part of the second signal.

The present disclosure describes the concept of operations and the medium access control protocols of a wireless communication system using code-division multiple access with interference avoidance (CDMA-IA) as its physical layer. The system can dynamically share a common band with other networks without a central radio resource controller. In one embodiment, the wireless communication system includes a plurality of radio nodes forming a wireless mesh network, wherein the pairs of radio nodes use, individually optimized, time division duplexing. At least one radio node includes a software-defined radio, a memory, and an electronic processor. The electronic processor is configured to control the software-defined radio to transmit a pilot signal and share various state information with the other nodes of the network. The shared information includes local spectrum occupancy and node connectivity sets. The pervasive sharing of spectrum occupancy among all nodes enables the usage of the shared band to be maximized.

Various aspects described herein relate to techniques for using orthogonal demodulation reference signals (DMRSs) for downlink control channels in wireless communications systems. In an aspect, a method for a user equipment (UE) includes receiving one or more DMRSs over a multi-symbol downlink control channel. The method may further include identifying a time-first control channel element (CCE)-to-resource element group (REG) mapping for the multi-symbol downlink control channel, and identifying an orthogonal DMRS of the one or more DMRSs based on the time-first CCE-to-REG mapping, and decoding the multi-symbol downlink control channel based on at least the identified orthogonal DMRS.

Aspects of the present disclosure provide methods and devices for multiple access downlink transmissions from a network side component to one or more User Equipment (UE) or multiple access uplink transmissions from two or more UEs to a network side component. In a downlink direction, a network side device generates, for each sub-carrier of the block of sub-carriers, a single constellation point from one or more bits of a multi-bit symbol, from each of multiple layers. In an uplink direction, each UE maps at least one bit from one or more layers of multi-bit symbols onto a subset of a block of sub-carriers. The two or more UEs collectively transmit on the block of sub-carriers.

Method of scrambling signals, transmission point device, and user equipment using the method are provided. The method includes: sending an ID table to a user equipment through higher layer signaling, the ID table being a subset of the whole ID space and containing available IDs for the user equipment; notifying the user equipment an ID in the ID table to be used through physical layer signaling or UE specific higher layer signaling; generating a random seed based on the notified ID; initializing a scrambling sequence by the random seed; and scrambling the signals with the initialized scrambling sequence. The method of the disclosure, by combining physical layer signaling and higher layer signaling, may notify the used group ID and the blind detection space to a UE, wherein the blind detection for the UE is enabled and the signaling overhead is reduced.

A user equipment (UE) can include processing circuitry coupled to memory. To configure the UE for New Radio (NR) communications above a 52.6 GHz carrier frequency, the processing circuitry is to decode radio resource control (RRC) signaling to obtain a cyclic shift value in time domain. The cyclic shift value is associated with a demodulation reference signal (DM-RS) antenna port (AP) of a plurality of available DM-RS APs. A single carrier based waveform DM-RS sequence corresponding to the DM-RS AP is generated using a base sequence and the cyclic shift value. The single carrier based waveform DM-RS sequence is encoded with uplink data for transmission to a base station using a physical uplink shared channel (PUSCH) using a carrier above the 52.6 GHz carrier frequency.

The present disclosure discloses a method and a system for providing a code cover to Orthogonal Frequency Division Multiplexing (OFDM) symbols in a multiple user system. A data sequence is received from each of a plurality of users. Further, a reference sequence is generated for the data sequence of each of the plurality of users. Each of the reference sequence is multiplied with a code cover which are orthogonal to each other. Each of the reference sequence is time-multiplexed with corresponding data sequence, to generate a corresponding multiplexed sequence. Further, a Discrete Fourier Transform (DFT) is performed on each of the multiplexed sequence to generate a corresponding DFT-spread-Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) symbol. Lastly, the corresponding DFT-s-OFDM symbol is processed for transmitting over corresponding one or more channels.

A communication unit for performing soft-decision demodulation comprises a receiver that receives a transmitted signal conveying a first set of bits comprising k bits selected from a set of 2.sup.k possible signals. A demodulator comprises a bank of 2.sup.k correlators that detects a transmission of each possible transmitted signal, and outputs 2.sup.k magnitudes of correlator outputs, based on the detected possible transmitted signals, as a first set of inputs. A-de-mapper circuit receives the first set of inputs and determines derived from a plurality of aggregated correlator output magnitude distributions of the first set of inputs, wherein the plurality of aggregated correlator output magnitude distributions is fewer than 2.sup.2k; and calculates therefrom a first set of aposteriori soft bits comprising k soft bits. In this manner, high quality soft-decisions can be obtained in a robust and practical manner.

Techniques for transmitting and receiving wireless communications over an unlicensed radio frequency spectrum band are disclosed, including techniques for transmitting and receiving system information blocks over the unlicensed radio frequency spectrum band, techniques for gaining access to the unlicensed radio frequency spectrum band by performing extended clear channel assessments (ECCAs), techniques for transmitting and receiving synchronization signals and reference signals over the unlicensed radio frequency spectrum band, techniques for identifying starting times of downlink transmissions over the unlicensed radio frequency spectrum band, techniques for transmitting and receiving clear channel assessment (CCA)-exempt transmissions over the unlicensed radio frequency spectrum band, techniques for performing random access over the unlicensed radio frequency spectrum band, and techniques for dynamically modifying a transmission mode over the unlicensed radio frequency spectrum band.