580results about "Pulse generation with predetermined statistical distribution" patented technology

A CDMA modem includes a modem transmitter having: a code generator which provides an associated pilot code signal and which generates a plurality of message code signals; a spreading circuit which produces a spread-spectrum message signal by combining each of the information signals with a respective one of the message code signals; and a global pilot code generator that provides a global pilot code signal to which the message code signals are synchronized. The CDMA modem also includes a modem receiver having an associated pilot code generator and a group of associated pilot code correlators for correlating code-phase delayed versions of the associated pilot signal with a receive CDM signal to produce a despread associated pilot signal. The code phase of the associated pilot signal is changed responsive to an acquisition signal value until a pilot signal is received. The associated pilot code tracking logic adjusts the associated pilot code signal in phase responsive to the acquisition signal so that the signal power level of the despread associated pilot code signal is maximized. Finally, the CDMA modem receiver includes a group of message signal acquisition circuits, each including a plurality of receive message signal correlators which correlate respective local received message code signal to the CDM signal to produce a respective despread received message signal.

A frequency jittering circuit modulates a hysteretic band of an oscillator such that the clock generated by the oscillator has a jitter frequency, and thus a switching mode power supply operative on the clock will have a jittering switching frequency.

Circuits and methods of dynamic modulation are disclosed. A dynamic modulator is used to reduce measurable conducted and / or radiated electromagnetic interference (EMI). The dynamic modulator is configured to generate either a set of optimal frequency modulation depths or discrete frequencies or both, and dynamically selects them to use over a series of programmable time durations (dwell time). Together with the utilization of Peak, Average or Quasi-Peak (QP) method of measurement, the dynamic modulator can reduce the spectral amplitude of EMI components, in particular the lower harmonics, to effectively pass regulatory requirements. In alternative embodiments, the dynamic modulator is used in a closed loop system to continuously adjust the frequency and the duty cycle of a PWM signal to reduce conducted and / or radiated EMI.

A semiconductor device includes a latency signal generating circuit for generating a latency signal corresponding CAS latency by measuring a delay amount reflected at a delay locked loop and reflecting the measured delay amount at a read command signal, and a delay locked loop for controlling an internal clock signal applied to the latency signal generating circuit corresponding to the read command and the latency signal. The semiconductor device includes an internal clock signal generating block configured to generate an internal clock signal, a latency generating block configured to generate a latency signal by synchronizing a read command signal with the internal clock signal at a time corresponding to a CAS latency value and a measured delay value, and an input controlling block configured to activate the reference clock signal using an external clock signal in response to the read command signal and the latency signal.

A method and apparatus for testing the random numbers generated by a random number generator in real time. As a series of random numbers are generated, a plurality of the last numbers are stored, then the stored random numbers are shifted by predetermined amounts to obtain a special kind of dot product of bit sequences between the stored random numbers and the shifted random numbers. The average autocorrelation values are computed each time a new random bit is generated. Thereafter, it is determined whether the generated random numbers are not sufficiently random by comparing the average autocorrelation values to predetermined acceptance ranges.

A clock and data recovery circuit includes a phase-shift circuit having a switch, which receives multiphase clocks, for selecting and outputting a plurality of clock pairs from among the multiphase clocks, and a plurality of interpolators, which receive the plurality of clock pairs output from the switch, for outputting clock signals in which delay time is stipulated by time obtained by performing interior division of the phase difference between the clocks of the pair; a plurality of latch circuits which receive input data in common; a phase detecting circuit for detecting and outputting phase, with respect to the clock, of a transition point of the input data from the outputs of the plurality of latch circuits; a filter for smoothing the output of the phase detecting circuit; and a control circuit for controlling clock phase by outputting control signals for controlling the interpolators and / or switch of the phase-shift circuit based upon the filter output.

A pseudo-random number sequence output unit responsive to s (1≦s) number of prescribed positive integers q1, q2, . . . , qs, a prescribed real impulse constant r (−1<r<1), and a prescribed non-zero real constant C for outputting a pseudo-random number sequence of length N (1≦N), which output unit includes: an input acceptance section that accepts input of s (1≦s) number of real number sequence initial values Y1, Y2, . . . , Ys (−1<Y1<1, −1<Y2<1, . . . , −1 Ys<1), and s number of integer parameters p1, p2, . . . , ps (2≦p1, 2≦p2, . . . 2≦ps) for which q1 mod p1≠0, q2 mod p2≠0 . . . , qs mod ps≠0 respectively hold with respect to the prescribed positive integers q1, q2 . . . qs; a calculation section that uses the prescribed real impulse constant r, the prescribed non-zero real constant C, the sequence initial values Y1, Y2, . . . , Ys, the integer parameters p1, p2, . . . , ps, the prescribed positive integers q1, q2, . . . , qs and integers j (1≦j≦s), m (1≦m≦2N−2) and n (1≦n≦2N−1) to calculate from the recurrence formula Tp⁡(cos⁢ ⁢θ)=T⁡(p,cos⁢ ⁢θ)=cos⁡(p⁢ ⁢θ)yj⁡[1]=Yjyj⁡[m+1]=T⁡(pj,yj⁡[m])z⁡[n]=∏j=1s⁢T⁡(qj,yj⁡[n])a pseudo-random number sequence z′[1], z′[2], . . . , z′[N] of length N that satisfies z′⁡[1]=⁢C⁢∑j=1N⁢(-r)j⁢z⁡[j],z′⁡[2]=⁢C⁢∑j=1N⁢(-r)j⁢z⁡[j+1],⋮⁢z′⁡[N]=⁢C⁢∑j=1N⁢(-r)j⁢z⁡[j+N-1]; ⁢andan output section that outputs the pseudo-random number sequence z′[1], z′[2], . . . , z′[N]. A transmitter, receiver and communication system that utilize the output unit, a filter unit, a pseudo-random number sequence output method, transmission method, receiving method and filtering method are provided. A computer-readable data recording medium recorded with a program for operating the transmitter, receiver, communication system and implementing the output, transmission and receiving methods is also provided.

A spread spectrum clock generator (SSCG) control and inspection circuit provides a system and method for inspecting and controlling an external SSCG, and for verifying the modulation profile waveform of an external SSCG. An electronic circuit is included that can check for the presence of an optimal SSCG modulation profile in product subsystems, and in attached modular systems, including electronic plug-in features such as internal network adapters and cartridges. In one mode of the invention, an electronic circuit ensures continued radiated emissions compliance for field replaceable units or consumable parts within a product, such as a printer, a scanner, or a combination (or all-in-one) printer / scanner. In another mode of the invention, an electronic circuit may also act as a secondary security device for consumable products, such as toner cartridges or ink jet cartridges. In yet another mode of the invention, an electronic circuit may also adjust the attached SSCG clock.