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.

Disclosed herein are methods and systems for processing signals from multiple users at an antenna array, and to provide beamforming for transmitting to those multiple users, and more particularly for channel estimation and wireless signal recovery in wireless networks carrying transmissions in the millimeter wave frequency bands to enable such beamforming. Such methods and systems enable MIMO communications at millimeter wave frequencies for multiple users communicating with a MIMO antenna system, such as a massive MIMO multi-antenna system (multi-antenna arrays that consist of hundreds of antenna elements). Such methods and systems may characterize the communications link (i.e., channel) at that frequency band, and directly provide a precoding matrix for beam steering towards a particular user that is in communication with the antenna system.

A method and a device allowing a terminal to receive a signal in a wireless communication system, according to one embodiment of the present invention, configure a search space set constructed in a hierarchical structure, and can monitor control channel candidates in the configured search space set. Particularly, when the hierarchical structure is constructed, a control channel candidate of a lower aggregation level (AL) in the search space set is randomly arranged on the basis of a control channel candidate of a top AL in the search space set, wherein a portion or the entire area of the control channel candidate of the lower AL can be arranged so as to overlap the control channel candidate of the top AL.

A method for receiving, by a terminal, a physical downlink control channel (PDCCH) signal in a wireless communication system, according to one embodiment of the present invention, comprises the steps of: determining a complexity of channel estimation required to monitor PDCCH candidates on at least one control resource set (CORESET) in one slot; skipping the monitoring of some of the PDCCH candidates and monitoring only the remaining PDCCH candidates if the determined complexity of the channel estimation exceeds the channel estimation capability of a terminal; and receiving a PDCCH signal on the basis of a result of monitoring the remaining PDCCH candidates, wherein the complexity of the channel estimation may be determined on the basis of the resource element group (REG) bundle size set for each of the at least one CORESET. The UE is capable of communicating with at least one of another UE, a UE related to an autonomous driving vehicle, a base station or a network.

An apparatus and method are provided for Doppler estimation of a signal received over a time-varying transmission medium, the method including receiving the signal over a channel of the time-varying transmission medium; sampling a magnitude of the received signal repeatedly over time; identifying unidirectional threshold crossings of the sampled magnitude about a threshold magnitude relative to a mean magnitude; measuring differences between the sampled magnitude and the threshold magnitude for the identified crossings; analyzing the measured differences over time; estimating the time-varying nature of the channel based on the analyzed differences; and transmitting a signal indicative of the estimated time-varying nature.

Embodiments of the disclosure relate to a method for blind detection of a PDCCH and a terminal device. The method includes: when the number of PDCCH blind detections in at least one search space of a terminal device is greater than a maximum number of blind detections, the terminal device reduces the number of PDCCH blind detections in n UE-specific search spaces and/or m common search spaces in the at least one search space, the reduced number of PDCCH blind detections being less than or equal to the maximum number of blind detections; and the terminal device performs PDCCH blind detection in the at least one search space according to the reduced number of PDCCH blind detections. According to the method and the terminal device, the terminal device can allocate the number of blind detections more reasonably, and reduce the complexity of channel estimation of the terminal device.

The present disclosure provides a device and a method for determining detection information about search spaces, and relates to the field of communications technology. The method for determining detection information about search spaces includes, in a case that at least two search spaces are being detected by a UE and a sum of initial quantities of pieces of detection information about the at least two search spaces is greater than a total quantity of pieces of detection information supported by the UE, determining a first quantity of pieces of detection information about each of the at least two search spaces. A sum of the first quantities of pieces of detection information about the at least two search spaces is smaller than or equal to the total quantity of pieces of detection information. The detection information includes a PDCCH candidate or PDCCH channel estimate.

The present invention concerns a system for the blind demodulation of a linearly modulated digital telecommunication signal and comprising modules allowing the estimation, monitoring of the temporal variations and corrections in the value of the phases, amplitudes, frequencies, time offsets and a set of compensation filters of the propagation channel, characterized in that it comprises at least one hardware or hardware and firmware architecture comprising memories and one or more processing units for implementing a network of specific calculation blocks connected to each other, including a block for the blind synchronization of the signal allowing the estimation, monitoring and compensation of the delay of the signal and also making it possible to adapt the processing rate of the downstream chain (of the demodulation system) to the reduced cadence of one sample per symbol, a first block incorporates at least one module making it possible to estimate at least one of the parameters of the observed signals in order to subsequently evaluate the other parameters of the observed signals, by other calculation blocks of the network, at least a second specialized calculation block incorporates a decision module in order to calculate an error signal and retro-propagate the calculated errors to each of the preceding residual blocks.

Systems and methods for improving isolation between a cosite transmitter-receiver system. The transmitter may send a first plurality of transmit signals from multiple transmit ports. The first plurality of transmit signals may be related to one another by a first set of complex weights. The receiver may detect channel-impaired versions of the first plurality of transmit signals at one or more receive ports. The receiver may analyze channel-impaired versions of the first plurality of transmit signals to estimate channel state information. The transmitter may use the channel state information to determine a second set of complex weights which will reduce the power received at one or more ports of the receiver when applied to a second plurality of transmit signals. The second set of complex weights may vary with frequency.

Methods, systems, and devices for wireless communication are described. In some cases, due to blind decoding and channel estimation (CE) limits, one or more user equipment (UE) specific search sets may be pruned for blind decoding and/or CE purposes. For instance, after hashing a set of common decoding candidates to control channel elements (CCEs) within the control region, the UE specific search sets may be pruned so as to conform to the blind decode limitation, since a common search space has already occupied a portion of the total blind decode limit. Following pruning, the UE may hash the sets of UE-specific decoding candidates associated with the one or more UE specific search sets to CCEs within the control region. The UE may further prune UE specific search sets, based on CE limits, while reusing CE for overlapping hashed locations.