Abstract: The present disclosure describes over-the-air UL-DL reciprocity calibration of UEs. In some embodiments, the UE may perform the calibration at the UE, while in other embodiments the BS may determine the calibration parameters for a UE and send the parameters to the UE for implementation. The BS may explicitly or implicitly transmit an UL channel estimate to the UE for use with the DL channel estimate. The UE determine calibration parameters to implement at the UE based on the BS feedback. Alternatively, the BS may transmit UE calibration parameters determined as a byproduct if the BS's own calibration procedure. The UE may instead participate in a calibration procedure with another UE. Under any approach, the UE may implement in its RF chain the results of the calibration procedure.

Abstract: Wireless communications systems and methods related to over-the-air uplink-downlink (UL-DL) reciprocity calibration. A central unit transmits downlink (DL) calibration reference signal (RS) and a calibration request. The central unit receives, in response to the calibration request, a first uplink (UL) calibration RS and a first DL channel estimate associated with a first transmission point (TP) and a first wireless communication device. The central unit transmits a DL coordinated multipoint (CoMP) joint transmission signal according to an uplink-downlink (UL-DL) reciprocity calibration. The UL-DL reciprocity calibration is based on at least a first UL channel estimate based on the first UL calibration RS, the first DL channel estimate, a second UL channel estimate associated with a second TP and the first wireless communication device, and a second DL channel estimate associated with the second TP and the first wireless communication device.

Abstract: Methods, systems, and devices for wireless communication are described. A wireless device may communicate using a dynamic cyclic prefix (CP) length to reduce communications overhead. That is, the wireless device may use a CP length that is changeable for each data packet or listen-before-talk (LBT) frame. For example, the wireless device may initially communicate using a first CP length and then receive a dynamic CP indication for subsequent symbols in one or more data packets or LBT frames. The wireless device may then communicate using the different CP length based on the indication. In some examples, the indicated dynamic CP length may be based on a cell radius of a base station, a data direction, or the location of a user equipment (UE) in relation to the base station.

Abstract: Various aspects described herein relate to small cyclic delay diversity (SCDD) operation used in a wireless communication system (e.g., 5G New Radio). A method, a computer-readable medium, and an apparatus are provided. In an aspect, the method, computer-readable medium, or apparatus operates to identify a type of information for transmission, identify a rank associated with the type of information, and perform an SCDD precoding operation based at least in part on the identified type of information or the rank.

Abstract: Wireless communications systems and methods related to over-the-air uplink-downlink (UL-DL) reciprocity calibration. A central unit transmits downlink (DL) calibration reference signal (RS) and a calibration request. The central unit receives, in response to the calibration request, a first uplink (UL) calibration RS and a first DL channel estimate associated with a first transmission point (TP) and a first wireless communication device. The central unit transmits a DL coordinated multipoint (CoMP) joint transmission signal according to an uplink-downlink (UL-DL) reciprocity calibration. The UL-DL reciprocity calibration is based on at least a first UL channel estimate based on the first UL calibration RS, the first DL channel estimate, a second UL channel estimate associated with a second TP and the first wireless communication device, and a second DL channel estimate associated with the second TP and the first wireless communication device.

Abstract: Methods, systems, and devices for broadcast transmissions in wireless communication are described. A base station may transmit a control reference signal (CRS), a UE-specific reference signal (UERS), and broadcast data (e.g., broadcast physical downlink shared channel (PDSCH) data) in a broadcast downlink transmission. A UE may identify that the CRS and UERS are associated with the broadcast downlink data, and demodulate the broadcast downlink data in the broadcast downlink transmission based at least in part on the CRS and UERS. A UE may estimate a frequency offset based on a phase difference between the CRS and UERS, combine the CRS and UERS for use in a channel estimation, and demodulate the broadcast data based at least in part on the estimated frequency offset and channel estimation. The base station may provide signaling, such as dynamic or semi-static signaling, that indicates presence of both CRS and UERS.

Abstract: Over-the-air (OTA) phase synchronization for reciprocity-based coordinated multipoint (CoMP) joint transmission is disclosed. Phase synchronization reference signals (PSRS) are transmitted within a CoMP operation that can be used to determine the phase drifts of the transmit and receive chains of the base stations. These phase drifts can then be used to obtain a relative phase drift between the uplink and downlink channels. When estimating the uplink channel from the sounding reference signals (SRS), the relative phase drift may be applied to estimate the downlink channel as well. The OTA phase synchronization may be performed with a user equipment (UE)-assisted or inter-base station procedures.

Abstract: The present disclosure describes over-the-air UL-DL reciprocity calibration of UEs. In some embodiments, the UE may perform the calibration at the UE, while in other embodiments the BS may determine the calibration parameters for a UE and send the parameters to the UE for implementation. The BS may explicitly or implicitly transmit an UL channel estimate to the UE for use with the DL channel estimate. The UE determine calibration parameters to implement at the UE based on the BS feedback. Alternatively, the BS may transmit UE calibration parameters determined as a byproduct if the BS's own calibration procedure. The UE may instead participate in a calibration procedure with another UE. Under any approach, the UE may implement in its RF chain the results of the calibration procedure.

Abstract: Wireless communications systems and methods related to over-the-air uplink-downlink (UL-DL) reciprocity calibration. A central unit transmits downlink (DL) calibration reference signal (RS) and a calibration request. The central unit receives, in response to the calibration request, a first uplink (UL) calibration RS and a first DL channel estimate associated with a first transmission point (TP) and a first wireless communication device. The central unit transmits a DL coordinated multipoint (CoMP) joint transmission signal according to an uplink-downlink (UL-DL) reciprocity calibration. The UL-DL reciprocity calibration is based on at least a first UL channel estimate based on the first UL calibration RS, the first DL channel estimate, a second UL channel estimate associated with a second TP and the first wireless communication device, and a second DL channel estimate associated with the second TP and the first wireless communication device.

Abstract: Over-the-air (OTA) phase synchronization for reciprocity-based coordinated multipoint (CoMP) joint transmission is disclosed. Phase synchronization reference signals (PSRS) are transmitted within a CoMP operation that can be used to determine the phase drifts of the transmit and receive chains of the base stations. These phase drifts can then be used to obtain a relative phase drift between the uplink and downlink channels. When estimating the uplink channel from the sounding reference signals (SRS), the relative phase drift may be applied to estimate the downlink channel as well. The OTA phase synchronization may be performed with a user equipment (UE)-assisted or inter-base station procedures.

Abstract: Wireless communications systems and methods related to over-the-air uplink-downlink (UL-DL) reciprocity calibration. A central unit transmits downlink (DL) calibration reference signal (RS) and a calibration request. The central unit receives, in response to the calibration request, a first uplink (UL) calibration RS and a first DL channel estimate associated with a first transmission point (TP) and a first wireless communication device. The central unit transmits a DL coordinated multipoint (CoMP) joint transmission signal according to an uplink-downlink (UL-DL) reciprocity calibration. The UL-DL reciprocity calibration is based on at least a first UL channel estimate based on the first UL calibration RS, the first DL channel estimate, a second UL channel estimate associated with a second TP and the first wireless communication device, and a second DL channel estimate associated with the second TP and the first wireless communication device.

Abstract: Various aspects described herein relate to small cyclic delay diversity (SCDD) operation used in a wireless communication system (e.g., 5G New Radio). A method, a computer-readable medium, and an apparatus are provided. In an aspect, the method, computer-readable medium, or apparatus operates to identify a type of information for transmission, identify a rank associated with the type of information, and perform an SCDD precoding operation based at least in part on the identified type of information or the rank.

Abstract: Methods, systems, and devices for broadcast transmissions in wireless communication are described. A base station may transmit a control reference signal (CRS), a UE-specific reference signal (UERS), and broadcast data (e.g., broadcast physical downlink shared channel (PDSCH) data) in a broadcast downlink transmission. A UE may identify that the CRS and UERS are associated with the broadcast downlink data, and demodulate the broadcast downlink data in the broadcast downlink transmission based at least in part on the CRS and UERS. A UE may estimate a frequency offset based on a phase difference between the CRS and UERS, combine the CRS and UERS for use in a channel estimation, and demodulate the broadcast data based at least in part on the estimated frequency offset and channel estimation. The base station may provide signaling, such as dynamic or semi-static signaling, that indicates presence of both CRS and UERS.

Abstract: Methods, systems, and devices for wireless communication are described. A wireless device may communicate using a dynamic cyclic prefix (CP) length to reduce communications overhead. That is, the wireless device may use a CP length that is changeable for each data packet or listen-before-talk (LBT) frame. For example, the wireless device may initially communicate using a first CP length and then receive a dynamic CP indication for subsequent symbols in one or more data packets or LBT frames. The wireless device may then communicate using the different CP length based on the indication. In some examples, the indicated dynamic CP length may be based on a cell radius of a base station, a data direction, or the location of a user equipment (UE) in relation to the base station.

Abstract: Method, receiver and computer program product for decoding a coded data block received at the receiver are disclosed. A first plurality of coded data bits representing the coded data block are received. First soft information values are determined corresponding to respective ones of the received first plurality of coded data bits, wherein each of the soft information values indicates a likelihood of a corresponding coded data bit having a particular value. An attempt is made to decode the coded data block using the first soft information values. The first soft information values are compressed. The compressed first soft information values are stored in a data store. A second plurality of coded data bits representing the coded data block is received and second soft information values corresponding to respective ones of the received second plurality of coded data bits are determined. The compressed first soft information values are retrieved from the data store and decompressed.

Abstract: Method, receiver and computer program product for decoding a coded data block received at the receiver are disclosed. A first plurality of coded data bits representing the coded data block are received. First soft information values are determined corresponding to respective ones of the received first plurality of coded data bits, wherein each of the soft information values indicates a likelihood of a corresponding coded data bit having a particular value. An attempt is made to decode the coded data block using the first soft information values. The first soft information values are compressed. The compressed first soft information values are stored in a data store. A second plurality of coded data bits representing the coded data block is received and second soft information values corresponding to respective ones of the received second plurality of coded data bits are determined. The compressed first soft information values are retrieved from the data store and decompressed.

Abstract: Ranking systems are described. In an embodiment a large scale data center has peta bytes of items and a query engine is provided to find the top k most frequently occurring items. In embodiments, samples are taken from the data center at least until a specified number of samplings is met, or until a stopping rule is met. In examples, the samples form a sample sketch which is used to find the top k most frequently occurring items without the need to examine every item in the data center. In other examples, the number of samplings or stopping rule is varied to provide ranks or frequencies. In other embodiments the ranking system operates on items having values to find separators which divide the items into bins such that the proportion of the items in each bin is different. For example, a data set may be apportioned to different types of processor.

Abstract: Ranking systems are described. In an embodiment a large scale data center has peta bytes of items and a query engine is provided to find the top k most frequently occurring items. In embodiments, samples are taken from the data center at least until a specified number of samplings is met, or until a stopping rule is met. In examples, the samples form a sample sketch which is used to find the top k most frequently occurring items without the need to examine every item in the data center. In other examples, the number of samplings or stopping rule is varied to provide ranks or frequencies. In other embodiments the ranking system operates on items having values to find separators which divide the items into bins such that the proportion of the items in each bin is different. For example, a data set may be apportioned to different types of processor.