摘要:
Techniques for scheduling flows and links for transmission are described. Each link is an oriented source-destination pair and carries one or more flows. Each flow may be associated with throughput, delay, feedback (e.g., acknowledgments (ACKs)) and/or other requirements. A serving interval is determined for each flow based on the requirements for the flow. A serving interval is determined for each link based on the serving intervals for all of the flows sent on the link. Each link is scheduled for transmission at least once in each serving interval, if system resources are available, to ensure that the requirements for all flows sent on the link are met. The links are also scheduled in a manner to facilitate closed loop rate control. The links are further scheduled such that ACKs for one or more layers in a protocol stack are sent at sufficiently fast rates.
摘要:
A method and structure for equipping a cache with information to enable the processor to track and report whether a given speculative access causes prefetches and/or pollutions of the cache. Two types of events are tracked in one of two different ways: first by counting/tracking prefetch operations, either globally or on a per instruction address basis and then by counting/tracking cache pollutions, either globally or on a per instruction address basis.
摘要:
An automated design system for VLIW processors explores a parameterized design space to assist in identifying candidate processor designs that satisfy desired design constraints, such as processor cost and performance. A VLIW synthesis process takes as input a specification of processor parameters and synthesizes a datapath specification, an instruction format design, and a control path specification. The synthesis process also extracts a machine description suitable to re-target a compiler. The re-targeted compiler generates operation issue statistics for an application program or set of programs. Using these statistics, a procedure for searching the design space can extract internal resources utilization information that is used to determine new candidate processors for evaluation.
摘要:
Providing fairness-based metrics for managing inter-sector interference of a mobile AN is described herein. By way of example, accumulation of resource utilization messages (RUMs) at a sector of the mobile AN can be based at least in part on a performance metric of that sector as compared with one or more neighboring sectors. In at least one aspect, performance metrics of multiple sectors of the mobile AN can be aggregated and a RUM accumulation rate of each sector is determined based on the aggregated metric. Accumulation rates can further be updated periodically as sector and/or aggregated metrics of the mobile AN change. Accordingly, accumulation and utilization of RUMs is based on inter-sector fairness to optimize overall wireless communication quality of service for the mobile AN.
摘要:
To select a transmission mode to use for a data transmission via a MIMO channel from station A to station B, station A obtains channel information used for spatial processing and determines the age of this information. Station A selects one of multiple transmission modes based on the age of the channel information and possibly other information (e.g., the fading characteristic of the MIMO channel). To select rate(s) to use for the data transmission, station A obtains channel state information (CSI) indicative of the received signal quality for the MIMO channel, e.g., received SNRs or “initial” rates. Station A determines the age of the CSI and selects one or more “final” rates based on the CSI, the age of the CSI, the selected transmission mode, and possibly other information. Station A processes data in accordance with the selected transmission mode and final rate(s) and transmits the processed data to station B.
摘要:
Techniques and apparatus for embedding one or more bits of 802.11 Very High Throughput (VHT) information in existing IEEE 802.11 preamble fields are provided. As will be described herein, because different combinations of modulation techniques, coding schemes, and transmission lengths result in the same transmit time (e.g., in terms of symbol length), a clever choice of modulation, coding, and length may allow some extra information to be embedded in a legacy field for use by VHT stations. In this manner, the total VHT preamble transmission time may potentially be reduced, thereby increasing the efficiency of the physical layer (PHY). Moreover, the embedded bits may most likely be invisible to legacy stations, since the transmission time that such stations compute will be independent of these bits by design.
摘要:
Techniques for selecting rates for data transmission on eigenmodes of a MIMO channel are described. An access point transmits an unsteered MIMO pilot via the downlink. A user terminal estimates the downlink channel quality based on the downlink unsteered MIMO pilot and transmits an unsteered MIMO pilot and feedback information via the uplink. The feedback information is indicative of the downlink channel quality. The access point estimates the uplink channel quality and obtains a channel response matrix based on the uplink unsteered MIMO pilot, decomposes the channel response matrix to obtain eigenvectors and channel gains for the eigenmodes of the downlink, and selects rates for the eigenmodes based on the estimated uplink channel quality, the channel gains for the eigenmodes, and the feedback information. The access point processes data based on the selected rates and transmits steered data and a steered MIMO pilot on the eigenmodes with the eigenvectors.
摘要:
Techniques for using at least one of omni-directional and directional antennas for communication are described. A station may be equipped antenna elements selectable for use as an omni-directional antenna or one or more directional antennas. The station may select the omni-directional antenna or a directional antenna for use for communication based on various factors such as, e.g., whether the location or direction of a target station for communication is known, whether control frames or data frames are being exchanged, etc.
摘要:
To select a transmission mode to use for a data transmission via a MIMO channel from station A to station B, station A obtains channel information used for spatial processing and determines the age of this information. Station A selects one of multiple transmission modes based on the age of the channel information and possibly other information (e.g., the fading characteristic of the MIMO channel). To select rate(s) to use for the data transmission, station A obtains channel state information (CSI) indicative of the received signal quality for the MIMO channel, e.g., received SNRs or “initial” rates. Station A determines the age of the CSI and selects one or more “final” rates based on the CSI, the age of the CSI, the selected transmission mode, and possibly other information. Station A processes data in accordance with the selected transmission mode and final rate(s) and transmits the processed data to station B.