Asynchronous communication

About: Asynchronous communication is a research topic. Over the lifetime, 28159 publications have been published within this topic receiving 430451 citations.

Asynchronous Power Control Game with Channel Outage Constraints in Cognitive Radio Networks

Abstract: This study provides a general framework for distributed multi-user power control problems in cognitive radio (CR) networks over fading channels. Using a non-cooperative game with coupled constraints in CR and primary channel outages, the fundamental performance traits of power control for multiple CR users are analyzed in the present of multiple primary users (PUs) in fading environments for the first time. While the feasibility of target SINRs are always guaranteed in most studies for no-fading environments, the adopted channel outage model incorporates the probability that the SINR falls below a target threshold due to fast fading or interferences from other CR users. For the tractable analysis of the formulated problem, geometric programming approach is used to transfer it as a convex one. A dual decomposition approach is applied with layered structure for the constrained game, where each subproblem is full of economic interpretation. The properties of Nash Equilibrium (N.E.) for the proposed game are thoroughly investigated. An asynchronous distributed power control algorithm converging to the N.E. is designed, which ensures the robust implementation in fading environments. Finally, the simulation results and analysis are shown to enforce the effectiveness of the proposed algorithms for CR users over fading channels.

Declarative support for asynchronous methods

Abstract: Asynchronous methods and calls are produced automatically as a function of a declarative indication of intent. A method annotated with an asynchronous attribute or method call including a special asynchronous function can be identified. Subsequently, an asynchronous version of an identified synchronous method or call is generated automatically. Assistance is also provided for specifying intent.

On Dual-Rail Control Logic for Enhanced Circuit Robustness

Abstract: Ultra low-power design and energy harvesting applications require digital systems to operate under extremely low voltages approaching the point of balance between dynamic and static power consumption which is attained in the sub-threshold operation mode. Delay variations are extremely large in this mode, which calls for the use of asynchronous circuits that are speed-independent or quasi-delay-insensitive. However, even these classes of asynchronous logic become vulnerable because certain timing assumptions commonly accepted under normal operating conditions are no longer valid. In particular, the delay of inverters, often used as the so-called input 'bubbles', can no longer be neglected and they have to be either removed or properly acknowledged to ensure speed-independence. This paper presents an automated approach to synthesis of robust controllers for sub-threshold digital systems based on dual-rail implementation of control logic which eliminates inverters completely. This and other important properties are analysed and compared to the standard single-rail solutions. Dual-rail controllers are shown not to have significant overheads in terms of area and power consumption and are even faster in some cases due to the elimination of inverters from critical paths. The presented automated synthesis techniques are very efficient and can be applied to very large controllers as demonstrated in benchmarks.

Asynchronous conversion circuitry apparatus, systems, and methods

Abstract: Apparatus, systems, and methods operate to receive a sufficient number of asynchronous input tokens at the inputs of an asynchronous apparatus to conduct a specified processing operation, some of the tokens decoded to determine an operation type associated with the specified processing operation; to receive an indication that outputs of the asynchronous apparatus are ready to conduct the specified processing operation; to signal a synchronous circuit to process data included in the tokens according to the specified processing operation; and to convert synchronous outputs from the synchronous circuit into asynchronous output tokens to be provided to outputs of the asynchronous apparatus when the synchronous outputs result from the specified processing operation. Additional apparatus, systems, and methods are disclosed.

Method and system for synchronizing the internal clock of a mobile radio station with local time.

Abstract: Disclosed is a system and a method for setting an internal time corresponding to a standard time at a current location in a mobile station of an asynchronous scheme. The mobile station of the asynchronous scheme uses a Simple Network Time Protocol (SNTP), which is an application of a Network Time Protocol (NTP), allowing the mobile station to easily update internal time information using a synchronized time. The SNTP can provide a time value which can be used to accurately reset an internal time of the mobile station of the asynchronous scheme. By using the SNTP, the mobile station of the asynchronous scheme can obtain exact time information as in a CDMA network and update the mobile station's internal time with the time corresponding to an area in which a standard time is changed.