摘要:
Certain aspects relate to methods and apparatus for latency reduction for UEs in a RRC connected mode. During contention-based uplink access by groups of UEs within a subframe, an eNB may decode the received uplink transmission based, at least in part, on the assigned group of resources assigned to the UE and used for transmission. Additional orthogonalization techniques such as reduced TTI size can be used to reduce collisions among different users performing contention-based transmissions. Furthermore, when the eNB fails to successfully decode the uplink transmission, the eNB may identify the UE that sent the uplink transmission based on a detected reference signal and may transmit an uplink assignment to the identified UE.
摘要:
Long term evolution (LTE)/LTE-Advanced (LTE-A) deployments with unlicensed spectrum leverage more efficient LTE communication aspects over unlicensed spectrum, such as over WIFI radio access technology. In order to accommodate such communications, various uplink procedures may be modified in order to handle communications between licensed and unlicensed spectrum with LTE/LTE-A deployments with unlicensed spectrum.
摘要:
Methods, systems, and devices are described for effective deployment of coverage enhancements in applications involving carrier aggregation or reception-limited devices, or both. Different categories of user equipment (UE) may be configured to receive simultaneous broadcasts and unicasts differently according physical limitations of each category of UE. Several component carriers may be utilized, and each may employ the same or different coverage enhancement techniques. Differences in coverage enhancement techniques may be accounted for with numbers and timing of hybrid automatic repeat request (HARQ) processes, soft buffer partitioning, channel bundling, and/or transmission prioritization. UEs may determine to cease transmission of one or more component carriers based on different priorities assigned to the component carriers.
摘要:
Methods, systems, and devices are described for dynamic cell mode indication and reporting channel and interference feedback for dormant cells in a carrier aggregation environment. Indicators of cell mode for one or more secondary cells are sent using a transmission mechanism and may configure active or dormant sub-periods within the indicated periods. Indicators of cell mode for a secondary cell may be transmitted on a carrier of the primary cell, or the indicators may be transmitted on carriers of the secondary cell. Dormancy may also be indicated by the presence or absence of a cell mode indicator for predetermined time periods. When CSI measurements occur for a carrier of a dormant cell, the UE may report CSI for the dormant periods, suppress CSI reporting for the dormant periods, adjust a reporting frequency for the dormant periods, or report some types of CSI and not others for the dormant periods.
摘要:
Systems and methods providing an enhanced new carrier type (eNCT) operable to adapt cells of a wireless communication network for opportunistic behavior that adapts to the geo-temporal traffic distribution are disclosed. Embodiments of eNCT operation provide for transmission of downlink common channels by cells employing eNCT techniques only when needed. Base stations implementing eNCT techniques herein may transition between two or more operational states, such as an active state wherein full base station functionality is performed and a dormant state wherein limited base station functionality is performed, based upon geo-temporal traffic distribution within the network. Thus, when a base station is not actively serving a user equipment (UE), the downlink transmission by the base station, and resulting interference, may be reduced or even eliminated.
摘要:
Methods, systems, and devices are described for detection of one or more interfering signals in a particular frequency spectrum. Signal characteristics may be identified for a signal of interest in the spectrum, such as a signal that is desired to be received at a wireless communications device. Based at least in part on the characteristics, one or more interference detection opportunities may be identified, during which interfering signals in the spectrum may be detected. Interference detection opportunities may include, for example, periods when the signal of interest may be absent from the particular frequency spectrum. Transmissions in the frequency spectrum may be monitored during the interference detection opportunity to determine the presence of one or more interfering signals.
摘要:
Methods and apparatuses are described in which an unlicensed spectrum is used for Long Term Evolution (LTE) communications. One method includes performing a clear channel assessment (CCA) for an unlicensed spectrum in a current gating interval to determine whether the unlicensed spectrum is available for a transmission in a next transmission interval, and gating OFF the transmission in the unlicensed spectrum for the next transmission interval when the determination is that the unlicensed spectrum is unavailable.
摘要:
Methods, systems, and/or devices are described for are provided for transmission overload control and/or supervision of wireless devices. Tools and techniques may be provided for resolving issues associated with numerous wireless devices connected to a base station. For example, a transmission cycle for an uplink channel may be identified where the transmission cycle is discontinuous. Scheduling request and or Random Access Channel messages may be transmitted from a wireless device based on the discontinuous transmission cycle. Tools and techniques are also provided that may involve supervision of numerous wireless devices. Supervision may, for example, involve keep-alive messages transmitted in accordance with a timer. The supervision may be based on determination of, and transmissions related to, a list or lists of connected wireless devices. In some cases, the wireless devices may be delay tolerant. The wireless devices may include UEs that may have long sleep cycles and/or machine-type communications (MTC) devices.
摘要:
Time tracking in current communication systems may be traditionally based on common reference signals (CRS). However, in certain communication systems, CRS-based time tracking may be impossible to implement due to an absence of CRS in certain subframes or carriers. CRS-based time tracking may also be inappropriate to implement in certain communication systems such as a coordinated multipoint (CoMP) system where control and data may arrive from different cells, and therefore, a UE may assume a wrong cell for CRS-based time tracking. Accordingly, methods, apparatuses, and computer program products for wireless communication are provided in which additional UE specific reference signals (UE-RS) and/or channel state information reference signals (CSI-RS) are made available to the UE so that the UE may have improved channel estimation and/or time tracking performance.
摘要:
A method, an apparatus, and a computer program product for wireless communication are provided. The apparatus receives control information from a first cell, generates an uplink transmission to a second cell based in part on the received control information from the first cell, receives a transmission power setting based on the uplink transmission to the second cell, and transmits in uplink using the transmission power to the second cell.