225 results about "Unit delay" patented technology

An apparatus and method for providing a security function of frames transmitted between optical network terminals (OLTs) and optical network units (ONUs) in an Ethernet passive optical network (EPON) providing media access control (MAC) services are provided. The apparatus includes: a frame classifier distinguishing the type of a frame, and based on the logical link identifier (LLID) of the distinguished frame, determining whether or not the frame is a security link to which a security function is to be applied; a bypass unit delaying a no-security-function frame so that a processing time for converting the security-function-applied frame classified in the frame classifier into an encrypted frame is the same as a time for processing the no-security-function frame; and a parameter generation unit transmitting in relation to each of the LLIDs, a parameter set value including a security-function-application setting signal used in the encryption, decryption and authentication of the frame, a frame decryption signal, an encryption mode selection signal, and an authentication intensity adjustment signal.

Deskewing method and apparatus, and a data reception apparatus using the deskewing method and apparatus, in which the deskewing apparatus includes an up/down detection unit, a lower limit detection unit, an upper limit detection unit, a phase detection unit, and a buffer unit. The up/down detection unit samples a received data signal in response to a data sampling clock signal, a first edge sampling clock signal, and a second edge sampling clock signal and determines in which of first through third areas of the data signal the logic level of the data signal transitions by using the result of the sampling, wherein the data sampling clock signal, the first edge sampling clock signal, and the second edge sampling clock signal are sequentially activated. The lower limit detection unit detects a lower limit of the first area if the logic level of the data signal transitions in the first area. The upper limit detection unit detects an upper limit of the third area if the logic level of the data signal transitions in the third area. The phase detection unit determines a delay amount indicating the amount by which the data signal is to be delayed according to the upper limit detected by the upper limit detection unit and the lower limit detected by the lower limit detection unit. The buffer unit delays the data signal by the delay amount determined by the phase detection unit. The deskewing apparatus can optimize data sampling by efficiently reducing data skew. In addition, the deskewing apparatus can minimize data restoration errors by reducing an accumulation of jitter.

The exemplary embodiments provide a reconfigurable integrated circuit architecture having a predetermined, unit timing increment (or delay) for both data operations and data word transfers within every zone and between zones, which are independent of application placement and routing. An exemplary IC comprises a plurality of circuit zones, with each zone comprising: a plurality of composite circuit elements, a plurality of cluster queues, and a full interconnect bus. Each composite circuit element comprises: a configurable circuit element circuit and an element interface and control circuit, with the element interface and control circuit comprising an input queue and an output queue. Each cluster queue comprises an element interface and control having an input queue and an output queue. The full interconnect bus couples every output queue within the zone to every input queue within the zone. Any data operation performed by a composite circuit element, any data word transfer through a cluster queue, and any data word transfer over the first full interconnect bus, is completed within a predetermined unit time delay which is independent of application placement and application data routing on the reconfigurable IC.

A method for performing parallel digital-to-analog conversion of an n-bit digital input data signal at a frequency of f_s including receiving the n-bit digital input data signal; generating M−1 delayed input data signals, M being the number of parallel conversions channels, the M−1 delayed input data signals having respective increasing amount of unit delay, the digital input data signal and the M−1 delayed input data signals forming M digital signals; holding the M digital signals for a first time period; performing a data transformation of the M digital signals using an M×M Hadamard matrix; generating M (n+m)-bit transformed digital data signals; converting each of the M transformed digital data signals to M analog signals; and performing a reverse data transformation of the M analog signals based on the M×M Hadamard matrix to generate an output analog signal indicative of the n-bit digital input data signal.

A delay line receives an input clock signal and includes a cascaded plurality of unit delay circuits. A mode register set stores a value indicative of a column-address-strobe (CAS) latency of the memory device, and an adjustment circuit varies a delay time of the unit delay circuits according to the CAS latency stored in the mode register set. A phase detector detects a phase difference between the input clock signal and an output clock signal of the delay line, and a control circuit which controls an enabled state of the unit delay circuits according to an output of said phase detector.

A delay-lock loop (DLL) circuit and method that accept an input clock signal and a feedback clock signal, and provide the necessary additional delay to synchronize the feedback clock signal to the input clock signal. Unlike previous circuits and methods, a single synchronization step is sufficient, provided that the frequency of the input clock signal is stable. A circuit according to the invention includes an input clock terminal supplying an input clock signal, and a delay line driven by the input clock signal and supplying a plurality of intermediate clock signals delayed from the input clock signal by incremental unit delays. A clock multiplexer selects from among these intermediate clock signals, under control of a multiplexer control circuit, the clock signal that provides the necessary additional delay to synchronize the feedback clock signal to the input clock signal. The output clock signal from the clock multiplexer is distributed through the clock network to provide the distributed clock signal as well as the feedback clock signal.

The invention discloses a dynamic scheduling method for multi-runway flight getting in and out. The method comprises the following steps that flight delay cost is analyzed, and a flight delay cost minimization objective function for multi-runway flight getting in and out scheduling is provided; theoretic delay time is calculated, and flight delay time of different aircraft types is converted into delay time of unit delay cost; fairness of multi-runway scheduling is analyzed, and the objective function considering the fair factor is built; ordinary constrain conditions of multi-runway flight dynamic scheduling are provided; the multi-runway flight scheduling constrain conditions considering flight delay are designed; the dynamic scheduling problem of multi-runway flight getting in and out is solved by adopting the genetic algorithm, dynamic scheduling of multi-runway flight getting in and out is achieved, and the purposes of improving the runway using rate and reducing the flight delay cost are achieved. According to the method, influence on multi-runway scheduling caused by flight delay is sufficiently considered, and the purposes of improving the runway using rate and reducing the flight delay cost are achieved.

A data strobe signal generator according to the present invention includes a control unit, a pulse delay unit, a clock generator, and a data strobe output unit. The control unit generates a CAS latency signal and a preamble signal. The pulse delay unit delays a pulse signal for predetermined time and outputs a delayed pulse signal. The clock generator outputs a control clock signal. The data strobe output unit outputs a data strobe signal. The data strobe signal generator and the semiconductor memory device having the same according to the present invention generate a data strobe signal based on an adjustable preamble value, thereby ensuring the stabilized data output operation of a high-speed memory device.

Delay locked loop circuitry for generating a predetermined phase relationship between a pair of clocks. A first delay-locked loop includes a delay elements arranged in a chain, the chain receiving an input clock and generating, from each delay element, a set of phase vectors, each shifted a unit delay from the adjacent vector. The first delay-locked loop adjusts the unit delays in the delay chain using a delay adjustment signal so that the phase vectors span a predetermined phase shift of the input clock. A second delay-locked loop selects, from the first delay-locked loop, a pair of phase vectors which brackets the phase of an input clock. A phase interpolator receives the selected pair of vectors and generates an output clock and a delayed output clock, the amount of the delay being controlled by the delay adjustment signal of the first delay-locked loop circuitry. A phase detector compares the delayed output clock with the input clock and adjusts the phase interpolator, based on the phase comparison, so that the phase of the delayed output clock is in phase with the input clock. As a result, there is a predetermined phase relationship between the output clock and the input clock, the phase relationship being the amount of delay between the output clock and the delayed output clock. Different phase relationships between the input and output clock are possible depending on the number of unit delays used in the path of the, delayed output clock or the output clock.

An apparatus and method linearize a power amplifier in a transmitter by using a dual time alignment scheme. A first adjustable time delay unit delays a modulator signal input of a power amplifier. A first time delay estimator estimates a time delay between the delayed feedback signal and the reference signal, and adjusts the first adjustable time delay unit based on the estimated time delay between the delayed feedback signal and the reference signal. A second adjustable time delay unit delays the feedback signal. And a second time delay estimator estimates the time delay between the delayed feedback signal and the reference signal, and adjusts the second adjustable time delay unit based on the estimated time delay between the delayed feedback signal and the reference signal.

Clock synchronization and skew adjustment circuits are described that utilize varying unit delay elements in their delay lines in either a graduated or a stepped unit time delay arrangement, allowing a reduced circuit implementation and improved lock characteristics. These graduated or a stepped unit time delays allow reduction in the number of the fine unit delay elements of the delay lines by placing a fine delay element granularity at the most critical timings to sense and adjust for the portion of the clock signal time period that are high speed or critical. This allows clock synchronization and skew adjustment circuits to be implemented in an optimized manner that exhibits a reduced overall circuit size and power consumption, while having improved lock characteristics over a wide range of frequencies.

The DLL comprises a coarse delay line configured to have a plurality of unit delays and delay an reference dock to output a delayed clock, a fine delay line configured to delay the delayed clock to output a delayed output clock, a replica delay unit configured to delay the delayed output clock by an expected modeling value to output a feedback clock, a phase detection unit configured to compare a phase of the feedback clock with a phase of the reference clock to generate first to third phase detection signals based on a result of the comparison, a locking detection unit configured to output a locking signal by selecting a first locking detection signal or a second locking detection signal, and a control unit configured to control the coarse and fine delay lines in response to the locking signal and the first phase detection signal.

Phase locked loop integrated circuits include a phase detection circuit, a variable delay device and a delay control circuit. The variable delay device and delay control circuit provide improved characteristics by increasing the signal frequency bandwidth of the delay locked loop integrated circuit in a preferred manner. The phase detection circuit is configured to perform the functions of comparing first and second periodic signals and generating a phase control signal (e.g., VCON) having a first property (e.g., magnitude) that is proportional to a difference in phase between the first and second periodic signals. The delay control circuit is responsive to the phase control signal VCON and generates a delay control signal that is provided to the variable delay device. The delay control circuit may comprise a counter, a first comparator, a second comparator and a shift register. The variable delay device includes a variable delay line and a compensation delay device. The variable delay line may contain a string of unit delay devices and a string of switches that each have an input electrically coupled to an output of a corresponding unit delay device. Each of the unit delay devices in the string may provide a fixed delay or a variable delay that is influenced (e.g., increased) by changes (e.g., increases) in the magnitude of the phase control signal VCON.

A method of generating a noisy receive signal for testing the performance of a mobile wireless communication device is described. A signal generator unit generates a transmit signal that frequency hops among a set of carrier frequency channels in a cyclic pattern having a time duration T. A wireless channel emulator unit generates a receive signal by modifying the transmit signal and also generates an interference signal by modifying the receive signal. The wireless channel emulator unit delays the interference signal relative to the receive signal by an integer multiple of the time duration T. The receive signal and the interference signal are combined by a combiner unit to generate the noisy receive signal.

A delay locked loop (DLL) circuit includes an initial operation setting unit configured to generate an initial operation signal in response to a reference clock signal and an operation start signal; a shift register configured to generate a delay control code in response to the initial operation signal, a phase comparison signal, and an initial setting code; a delay line configured to delay the reference clock signal or a feedback clock signal in response to the initial operation signal and the delay control code, thereby generating a plurality of unit delay clock signals; and an initial delay monitoring unit configured to generate the initial setting code in response to the reference clock signal and the plurality of unit delay clock signals.

The invention relates to an RS485-bus-based intelligent cabinet communication method and system communication between master and slave devices. The master device is connected to at least one slave device by the RS485 bus and slave devices have different address numbers. The method comprises: S1, self definition of a communication protocol format and a command format in a communication protocol is carried out, wherein a preset field expresses a timestamp/user data; and S2, the master device obtains identity information of all the slave devices by following steps: the master device sends broadcast commands to all the slave devices, wherein the timestamps/user data in the broadcast commands at this time are used for identifying unit delay time; the slave devices determine the delay time of the slave devices based on the address numbers and the unit delay time and send return commands including the identity information of the slave devices after waiting with the local delay time after receiving the broadcast commands. Therefore, a conflict problem can be solved; and the master device can obtain addresses of all slave devices automatically without designation.

A method for controlling a delay time of a signal in a semiconductor device is disclosed, which comprises the steps of: a) applying a test mode pulse signal; b) generating N number of test mode selection signals which are synchronized with the falling edges of the test mode pulse signal to respond sequentially; c) sequentially regenerating the (N−1)th test mode selection signal after the Nth test mode selection signal is generated; and d) repeating step c, wherein an input signal inputted to the semiconductor device is delayed by a predetermined time to be outputted as an output signal only when first to the (N−1)th test mode selection signals are enabled, and the delayed times are different from each other according to the first to the (N−1)th test mode selection signals. In the method, delay degree of a predetermined signal can be freely adjusted in a test mode. Further, a desired delay degree can be set by means of an external signal, regardless of the number of unit delay devices constituting a delay circuit.

A data extracting circuit extracts data much more accurately at a much higher response speed. A clock transfer section propagates an input clock signal through unit delay devices thereof. An edge detecting section locates an edge of the clock signal, which edge is being propagated through the clock transfer section, for a time represented by a given edge of an input data signal. In response to an edge detection signal indicating the clock signal edge located, a clock selecting section selects one of outputs of the delay devices, and presents the output as a clock input to a latch.

Digital delay-locked loops (DLLs) and methods are provided for signal frequency multiplication. Analog delay elements of typical frequency-multiplying DLLs are replaced with digital and digitally-controlled elements including a variable delay line. The number of unit delay elements in the delay line can be selected to produce a desired output signal delay. Phase-mixing of multiple variable delay line outputs achieves finer delay-time adjustments.