摘要:
A switch mode power supply (SMPS) and method are provided. In particular, the present invention provides an SMPS in which data is encoded by manipulating voltage pulses on a primary side. The manipulated voltage pulses are then transferred over a transformer to a secondary side. Secondary side pulses generated in response to the primary side pulses are sensed and decoded by a detector. The present invention allows data to be transferred from the primary side to the secondary side without affecting output voltages.
摘要:
A method for reducing harmonic distortions and switching losses in a power factor correction circuit of a quasi-resonant voltage converter, wherein using data derived from the sensing a voltage impressed on the switching device in the power converter, a multitude of event times can be calculated that will align the timings of the drive circuitry of the power converter to those of the natural resonance transitions of reactive elements of the converter. An over-sampling of the voltage impressed on the switching device voltage allows accurate sensing of a “zero-current” cross-over condition in an inductance of the converter.
摘要:
A high resolution pulse width modulation (PWM) or voltage controlled output (DCO) generator is disclosed. The resolution is increased over that of the circuit clock by delaying the generated signal through a series of delays, all of which are controlled by a delay locked loop. The delays are a small fraction of the clock period, thus providing resolution greater than that of the circuit clock.
摘要:
A digital controller comprises two control paths each having an A/D converter. One of the two converters has a substantially higher sampling speed and lower resolution than the other. Thus, one is suitable to deal with the fast responses while the other is suitable to deal with the slow responses, and can replace high-speed high-resolution A/D converter which is high in both cost and power consumption.
摘要:
A power supply comprising a flyback converter and a controller is disclosed. The flyback converter drives a load when electrically coupled to an alternating current power source. The controller controls a soft switching during each switching time period of the flyback converter. Upon an initial switching time period, the controller determines each acceptable switching frequency for the subsequent switching time periods and selects one of the acceptable switching frequencies for soft switching the flyback converter over one or more switching time periods during a constant load.
摘要:
A communication system comprises a set of specialized backend servers 100 and groups of terminals (210, 220) connected through the Internet. Users of the communication system can make video calls and share text messages, images and video clips through the terminals (210, 220). The terminals in this system are organized into private terminal groups 200 of varying sizes. Each group has only one controller terminal 210 and one or more display terminals 220. Both types of terminals provide an easy-to-use graphic user interface for the user to access the communication services provided by the system. Communication and information sharing between any display terminals must be pre-authorized by their controllers. This communication system, while ensuring security and privacy, addresses the needs of caregiver groups that include caregiver professionals, family members and care receivers, to facilitate private conference calls, information sharing and caring activity coordination.
摘要:
Embodiments provide methods and systems wherein analyte concentration readings taken over a first period of time are collected and processed to determine one or more analyte concentration averages. The methods include collecting samples with a measurement system (e.g., a Blood Glucose Meter) over a first period of time, dividing the first period of time into smaller time increments, and calculating an average analyte concentration based on first sub-averages obtained from each of the smaller time increments. Systems for carrying out the analyte concentration averages are described, as are other aspects.
摘要:
A receiver-driven streaming method is provided. The method includes receiving an original coded video stream from a transmitter 102 at a receiver 104. An available bit rate is measured at the receiver 104. A request for a different coded video stream and a switching stream is sent from the receiver 104 to the transmitter 102 based on the available bit rate. The requested switching stream is received from the transmitter 102 at the receiver 104. The requested coded video stream is received from the transmitter 102 at the receiver 104. According to one embodiment, switching streams 132a-132f are stored separately from coded video streams 130a-130c, and each switching stream 132a-132f and coded video stream 130a-130c is stored in a separate track from each other. In this way, switching streams 132a-132f maybe generated offline. Also, the receiver 104 controls the streams provided by the transmitter 102 by requesting specific switching streams 132a-132f and coded video streams 130a-103c.
摘要:
A so-called “Virtual Clock” with varying frequency is provided for used by a multimedia streaming server to adapt its transmission rate dynamically to changing network conditions. The “Virtual Clock” system and method of the present invention compensates for a potential limitation of the Internet Real-time Transmission Protocol (RTP), that stamps every packet it delivers with a timestamp and expects the server using this timestamp to schedule the transmission of this particular packet accordingly. Consequently, the transmission rate is pre-determined by the encoded multimedia content when RPT is used. Using the “Virtual Clock” of the present invention, the streaming server has a mechanism to overcome this RTP limitation and can conduct transmission rate adaptation in a way that can balance the bandwidth requirement of the content with the bandwidth availability of the network.
摘要:
A circular buffer, i.e., a chain of buffers forming a circle, is provided for managing packet loss detection in Internet streaming. The detection latency is determined by the size of the buffer chain, which can be dynamically adapted to network conditions and application requirements. The present invention can achieve reasonable detection accuracy.