Certain aspects of the present disclosure relate to methods and apparatus for implementing a data transmission scheme for Narrow-Band Internet of Things (NB-IoT). A User Equipment (UE) combines pairs of antenna ports to generate at least first and second combined antennas ports. The UE receives reference signals transmitted in a narrow band region of a larger system bandwidth, and for each combined port, adds the references signals received on resource elements (REs) of each of the combined pair of antenna ports. The UE determines channel estimates for each combined antenna port based on the added reference signals for the combined port.

Techniques for scrambling sequence generation may provide scrambling for a reference signal, a control signal, or a data signal that is independent of a center frequency of a wireless system bandwidth. Generated scrambling sequences may allow for demodulation of signals in which a synchronization channel does not share a same center frequency as the wireless system bandwidth.

In a method of sending a frame using a cyclic shift diversity (CSD) sequence, a wireless device generates a frame comprising a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal (L-SIG) field, a repeated legacy signal (RL-SIG) field, an extremely high throughput signal A (EHT-SIG A) field, and an extremely high throughput signal B (EHT-SIG B) field. The wire device sends the frame through a set of transmit antennas by performing cyclic shift over the fields according to a CSD sequence. The number of transmit antennas is greater than 8. The number of cyclic shift diversities in the CSD sequence is equal to a number of the transmit antennas, and each cyclic shift diversity has a value that is a multiple of 12.5.

A method and apparatus for generation of orthogonal training signals for transmission in an antenna array are described. In this embodiment, a set of P training signals is generated. The generation of the P training signals includes generating a first set of Zadoff-Chu sequences, where the first set of sequences is based on a first reference Zadoff-Chu sequence and first subsequent Zadoff-Chu sequences, where each one of the first subsequent Zadoff-Chu sequences is a cyclic shift of the first reference Zadoff-Chu sequence. A second set of sequences is generated based on a second reference sequence and second subsequent sequences that are cyclic shift of the second reference sequence. The P training signals are determined based on the first set of sequences and the second set of sequences. The training signals are then transmitted through a plurality of transmit paths of a base station towards a wireless network.

In an ISS process, the initiator sends a first SSW frame in different sector directions by sequentially using an antenna in m antennas, where m is not less than 1 and is less than or equal to N, and in an RSS process, the initiator receives a second SSW frame in a parallel (e.g., simultaneous) omnidirectional manner by using M antennas, where the second SSW frame is sent by a responder in different sector directions, each second SSW frame carries information used to indicate a first SSW frame with best quality in the ISS process, and the M antennas include at least the m antennas, and determines an optimal transmit beam in the ISS process based on the received second SSW frame.

Systems and methods for unified facility communications systems with device location are provided. One system embodiment comprises: a master unit and a plurality of remote antenna units defining a DAS. The master unit communicates with a base station to receive a base station downlink RF signal and to transmit a base station uplink RF signal. The remote antenna units radiate a remote downlink RF signal into a coverage area and receive a remote uplink RF signal from the coverage area. The master unit comprises uplink and downlink circuitry to transport user device communications, and a facility supervisory module to process facility device traffic associated with wireless facility assets in the coverage area. Facility device traffic is transported via the remote antenna units. Within the master unit, user device communications is routed via the uplink and downlink circuitry and facility device traffic is routed via the facility supervisory module.

According to an aspect, a wireless node selects a set of reference signal antenna ports for use in transmitting data to other wireless nodes in a given transmit time interval, from a plurality of sets of reference signal antenna ports that are available for use and that include reference signal antenna ports having different reference signal densities in the frequency and/or time dimension. The wireless node sends a message to a second wireless node indicating a reference signal assignment and including an indication of the selected set of reference signal antenna ports.

Provided is a transmitter which improves the flexibility of SRS resource allocation without increasing the amount of signaling for notifying the cyclic shift amount. In the transmitter, with regard to each basic shift amount candidate group having a basic shift amount from 0 to N−1, a transmission control unit (206) specifies the actual shift amount imparted to a cyclic shift sequence used in scrambling a reference signal transmitted from each antenna port, said specification being performed based on a table in which cyclic shift amount candidates correspond to each antenna port, and based on setting information transmitted from a base station (100). With regard to basic shift amount candidates for shift amount X, the table differentiates between an offset pattern comprising offset values for cyclic shift amount candidates corresponding to each antenna port and an offset pattern corresponding to basic shift amount candidates of X+N/2.

Methods, systems, and devices for group-specific resource indications in mobile communication systems are described. An exemplary method for wireless communication includes determining, by a network node, an association among one set of one or more reference signals (RSs) and one or more groups, where each of the one or more RSs is associated with a usage or a time-domain behavior, and transmitting, to the terminal, a signaling message comprising the association. Another exemplary method for wireless communication includes determining, by the network node, a reference signal (RS) configuration, wherein the RS configuration comprises an association between one or more target RSs and a spatial granularity, and transmitting, to a terminal, a message comprising the RS configuration.

Presently disclosed are systems and methods for beamforming training in WLANs. In various embodiments, there are unified MIMO beamforming training procedure, which includes a training period in which an initiator transmits multiple unified training frames for performing a transmit-beamforming training of the initiator and a receive-beamforming training of one or more responders; a feedback period in which each responder replies with a beamforming-feedback response; and an acknowledgement period during which the initiator transmits respective acknowledgement frames to the one or more responders from which responses were received. Rules for restricted random access in various slots of the feedback period may be implemented, to address response contention between multiple qualifying responders.