Sleep (system call)

About: Sleep (system call) is a research topic. Over the lifetime, 2633 publications have been published within this topic receiving 27806 citations. The topic is also known as: Sleep() & sleep().

Method and apparatus for compensating for frequency drift in a low frequency sleep clock within a mobile station operating in a slotted paging mode

Abstract: A method and apparatus is described for tracking the length of a sleep period within a mobile station using a sleep clock to precisely calibrate portions of the sleep period. The sleep period subdivided into a sequence of sub-periods each of known duration wherein the durations of the sub-periods are not necessarily integer multiples of cycles of the sleep clock. Elapsed time is tracked within each individual sub-period of the sleep period using an integer sleep counter which tracks whole cycles of the sleep clock. Then any remaining fractional portions of the cycles of the sleep mode clock not accounted for by the integer sleep counter are tracked using a fractional sleep counter. The fractional sleep counter accumulates remaining fractional portions of sleep mode cycles from one sub-period to the next. A method and apparatus is also described for estimating frequency drift with a sleep clock signal used during a slotted paging mode of operation of a wireless mobile station. An initial frequency of the sleep clock signal is determined following power-up of the mobile station. A fixed frequency drift compensation factor representative of a difference between the initial frequency of the sleep clock signal and a predetermined nominal frequency is then determined. A dynamic frequency error compensation factor representative of a difference between the initial frequency and a current frequency of the slow clock signal is estimated. Then, throughout the slotted mode of operation, new values for the dynamic frequency compensation factor are iteratively determined by using a loop filter.

System and method for controlling state transition in sleep mode and awake mode in a broadband wireless access communication system

Abstract: A broadband wireless access communication system having a sleep and an awake mode. A subscriber station controls the sleep mode upon receiving a denial response of a base station to a sleep request from the subscriber station to the base station. If the denial response from the base station is received, the subscriber station retransmits a sleep request to the base station after a lapse of waiting duration. If the denial response from the base station is received, the subscriber station holds retransmission of a sleep request to the base station until an unsolicited response to the sleep request is received from the base station.

Power management for wireless devices

Abstract: In some embodiments, a method to manage power in a wireless communication device, comprises in a wireless networking adaptor, changing an operational status of a wireless networking adaptor to a sleep mode and transmitting a sleep message from the wireless networking adaptor to a host driver in an electronic device coupled to the networking adaptor, in the electronic device, determining whether a sleep duration specified in the sleep message exceeds a threshold, in response to a determination that the sleep duration specified in the sleep message exceeds a threshold implementing a selective suspend operation on the electronic device, and monitoring for a wake event, and in response to a determination that the sleep duration specified in the sleep message does not exceed a threshold, flushing one or more bulk IN buffers, and monitoring for a wake event.

The use of entertainment and communication technologies before sleep could affect sleep and weight status: a population-based study among children.

Abstract: Short sleep duration and poor sleep quality have been demonstrated to be associated with childhood obesity. It has been suggested that electronic entertainment and communication devices (EECDs) including TVs, computers, tablets, video games and cell phones interfere with sleep in children and youth. The aim of this study was to assess the impact that the use of EECDs in the hour before bedtime has on sleep and weight status to inform sleep promotion interventions and programs to prevent childhood obesity. A provincially representative sample of 2334 grade 5 children and their parents in Alberta, Canada was surveyed. Parents reported their child’s bedtime and wake-up time along with how often their child snored, felt sleepy during the day, woke-up at night and woke-up in the morning feeling unrefreshed. Sleep duration, sleep quality and sleep efficiency were derived from these indicators. Parents also reported on the presence of EECDs in their child’s bedroom, while children reported use of EECDs during the day and frequency of using each of these devices during the hour before sleep. The height and weight of children were measured. Multivariable mixed effect linear and logistic regression models were used to determine how sleep duration, sleep quality, sleep efficiency and weight status are influenced by (i) access to EECDs in children’s bedrooms, (ii) use of EECDs during the hour before sleep, and (iii) calming activities specifically reading during the hour before sleep. Sleep duration was shorter by −10.8 min (cell phone), −10.2 min (computer) and −7.8 min (TV) for those with bedroom access to and used these EECDs during the hour before sleep compared to no access and no use. Good sleep quality was hindered by bedroom access to and use of all EECDs investigated during the hour before sleep, particularly among users of cell phones (OR = 0.64, 95% CI: 0.58–0.71) and computers (OR = 0.72, 95% CI: 0.65–0.80). Very good sleep efficiency was decreased by access to and frequent use of a TV (54%), cell phone (52%), tablet (51%) and video games (51%). Odds of obesity were doubled by bedroom access to and use of a TV and computer during the hour before sleep. Children who rarely read a printed book in the bedroom during the hour before sleep had a shorter sleep duration and poorer sleep quality and sleep efficiency compared to their peers. Having access to an EECD in the bedroom was associated with increased obesity despite frequently reading during the hour before sleep. Our findings suggest that sleep duration, sleep quality, sleep efficiency and weight status are better among children who do not have EECDs in the bedroom and frequently read a book during the hour before sleep as opposed to those who use EECDs during this hour. Education of limits against EECD use by parents may improve sleep outcomes. These findings will inform health promotion messages and may give rise to national recommendations regarding EECD use. ClinicalTrials.gov NCT01914185 . Registered 31 July 2013 Retrospectively registered.

Low leakage and data retention circuitry

Abstract: An integrated circuit includes first circuitry and sleep transistor circuitry. The first circuitry receives input signals and processes the input signals. The first circuitry also retains data in a sleep state that has low leakage. The sleep transistor circuitry is coupled to the first circuitry and receives a sleep signal that has a negative voltage. The sleep circuitry reduces power consumption of the first circuitry in the sleep state to have low leakage based on the sleep signal while retaining the data in the first circuitry.