The present disclosure provides a method and device for multi-antenna transmission in UE and base station. The user equipment receives a first wireless signal at first; then transmits a second wireless signal, and monitors a first signaling in a first sub-time resource pool. Wherein the first wireless signal is transmitted by K antenna port group(s) and the second wireless signal is used to determine the first antenna port group. The first antenna port group is one of the K antenna port group(s). The first sub-time resource pool is reserved to the first antenna port group, or the index of the first antenna port group is used to determine the first sub-time resource pool. One antenna port group includes positive integer number of antenna ports, and the K is a positive integer greater than 1. The disclosure reduces the complexity of blind detection of downlink signaling by the UE.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may identify an indication of an amount of remaining energy for the UE. In some cases, the UE may identify an indication of a temperature of the UE. In some cases, the UE may determine a constraint indicator based on the amount of remaining energy for the UE or the temperature of the UE. The UE may then transmit the constraint indicator to a base station via physical layer signaling. According to another embodiment, the UE may determine an alternative transmission mode based on the amount of remaining energy for the UE or the temperature of the UE. The UE may then transmit an indicator of the alternative transmission mode to the base station via physical layer signaling.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a wireless communication device may determine that a threshold is satisfied with regard to a search space set mapping, for a plurality of search space sets, for a slot of a downlink control channel, wherein the threshold relates to at least one of: a slot-based control channel element limit, or a slot-based blind decode limit; and perform a mapping of or monitor a subset of search space set occasions, of a search space set of the plurality of search space sets, in the slot in connection with determining that the threshold is satisfied. Numerous other aspects are provided.

Methods and systems are described for frequency domain correction, time domain correction, and combinations thereof. Each Long Term Evolution (LTE) uplink residual frequency offset can be determined with less than 1 part per billion accuracy simultaneously and used for frequency offset correction. The disclosed method utilizes the same modulated signals for data and control as the 3GPP LTE wireless standard and can be embedded directly into the base station (downlink) PHY without additional hardware. The use of the disclosed methods provide multiple ways to simultaneously improve the uplink data throughput for every user in an LTE multiple access wireless system.

The present invention provides a signal sending apparatus, a signal detection apparatus, a signal sending and detection system, a signal sending method, and a signal detection method. The apparatus determines a time unit that is in each time window and that is used to transmit a synchronization signal, and transmits the synchronization signal in the determined time unit in each time window. Therefore, a synchronization signal is always located in a time unit that has a fixed location in each time window, so that a device at a receive end needs to perform detection only in a fixed time unit in each time window, thereby reducing complexity of designing and detecting the synchronization signal.

According to one embodiment of the present invention, at least two transmission-reception beam pairs for control information between a terminal and a base station are set, and the terminal performs a blind detection for the control information by using the at least two transmission-reception beam pairs, thereby enabling the control information to be more strongly and efficiently transmitted and received.

The present disclosure provides a method and device for multi-antenna transmission in UE and base station. The user equipment receives a first wireless signal at first; then transmits a second wireless signal, and monitors a first signaling in a first sub-time resource pool. Wherein the first wireless signal is transmitted by K antenna port group(s) and the second wireless signal is used to determine the first antenna port group. The first antenna port group is one of the K antenna port group(s). The first sub-time resource pool is reserved to the first antenna port group, or the index of the first antenna port group is used to determine the first sub-time resource pool. One antenna port group includes positive integer number of antenna ports, and the K is a positive integer greater than 1. The disclosure reduces the complexity of blind detection of downlink signaling by the UE.

A method by which a terminal receives downlink control information in a wireless communication system includes: receiving a reference signal for a control channel by a search space set in a control resource set; and receiving downlink control information of the control channel on the basis of the reference signal. The search space includes a plurality of control channel candidates respectively corresponding to one or at least two CCEs according to an aggregation level, the one or at least two CCEs respectively include a plurality of REGs, and the terminal performs blind detection for each of the plurality of control channel candidates, and it can be assumed that a reference signal for a predetermined control channel candidate, for which blind detection is currently being performed, is mapped to a first REG firstly located in a time domain among REGs included in the predetermined control channel candidate.

Methods, systems, and devices for wireless communications are described. A base station may identify time and frequency resources for a physical downlink shared channel (PDSCH) to be transmitted to a user equipment (UE) in a first transmission time interval (TTI). The base station may transmit configuration information for a control channel search space set in a second TTI. The second TTI may precede the first TTI. The configuration information may include an indication of an absence of a physical downlink control channel (PDCCH) transmission to send in the control channel search space set indicating the identified time and frequency resources for the PDSCH, and a set of time and frequency resources for the control channel search space set. The UE may receive the configuration information and identify the time and frequency resources allocated for the PDSCH in the second TTI, and receive the PDSCH transmission in the second TTI.

A communication device, including a receiver configured to receive a signal from a transmitter, the signal including a plurality of data symbols; and at least one processor configured to: obtain a channel estimate and an estimated carrier frequency offset based on a result of an interference detection indicating whether interference is detected in the plurality of data symbols, obtain a data symbol of the plurality of data symbols, obtain a compensated data symbol corresponding to the data symbol based on the estimated carrier frequency offset, obtain an equalized compensated data symbol by performing channel equalization on the compensated data symbol based on the channel estimate, and demodulate and decode the equalized compensated data symbol to obtain decoded data.