摘要:
Adaptive multi-band frequency calibration is provided for a phase-locked loop (PLL). A voltage controller oscillator (VCO) is initially selected nominally associated with first synthesized signal frequency, where the VCO is selected from a plurality of n VCOs, and each VCO is tunable across a band of synthesized signal frequencies. A lock detector compares a nominal first synthesized signal frequency to a reference signal frequency. In response to sensing a difference between the nominal first synthesizer and reference signal frequencies, an out-of-lock condition is asserted and a VCO is reselected from the plurality of n VCOs. A mid-point control voltage is supplied to a control voltage input of the reselected VCO. A difference is measured between a mid-point synthesized signal frequency and the reference signal frequency. If the difference is less than a first threshold, the reselected VCO is assigned to generate the first synthesized signal frequency.
摘要:
A system and method are provided for resynchronizing a transmission signal using a jitter-attenuated clock derived from an asynchronous gapped clock. A first-in first-out (FIFO) memory accepts an asynchronous gapped clock derived from a first clock having a first frequency. The gapped clock has an average second frequency less than the first frequency. The input serial stream of data is loaded at a rate responsive to the gapped clock. A dynamic numerator (DN) and dynamic denominator (DD) are iteratively calculated for the gapped clock, averaged, and an averaged numerator (A and an averaged denominator (AD) are generated. The first frequency is multiplied by the ratio of AN/AD to create a jitter-attenuated second clock having the second frequency. The FIFO memory accepts the jitter-attenuated second clock and supplies data from memory at the second frequency. A framer accepts the data from the FIFO memory and the jitter-attenuated second clock.
摘要翻译:提供了一种系统和方法,用于使用从异步间隔时钟导出的抖动衰减时钟重新同步传输信号。 先进先出(FIFO)存储器接收从具有第一频率的第一时钟导出的异步间隔时钟。 间隔时钟的平均第二频率小于第一频率。 数据的输入串行流以响应于有间隙的时钟的速率加载。 对于有间隙的时钟进行迭代计算动态分子(DN)和动态分母(DD),得到平均分子(A和平均分母(AD)),第一个频率乘以AN / AD 创建具有第二频率的抖动衰减的第二时钟,FIFO存储器接受抖动衰减的第二时钟并以第二频率从存储器提供数据,成帧器接收来自FIFO存储器的数据和抖动衰减的第二时钟。
摘要:
A method is provided for synthesizing signal frequencies using low resolution rational division decomposition in a frequency synthesis device. An integer numerator (n) and an integer denominator (d) ratio is reduced; n/d=IO(NO/DO)=IO+NO/DO=(IO+1)−(DO−NO)/DO, and where NO/DO
摘要翻译:提供一种用于在频率合成装置中使用低分辨率有理分解分解合成信号频率的方法。 减小整数分子(n)和整数分母(d)比率; n / d = IO(NO / DO)= IO + NO / DO =(IO + 1) - (DO-NO)/ DO,NO / DO <1,NO和DO为整数。 NO减少; (Nn / Dn)= In + Nn / Dn =(In + 1) - (Dn-Nn)/ Dn,其中In,Nn和Dn为整数,Nn / Dn <1。 In,Nn和Dn用于创建最终的分子除数。 DO减少; Nd = Dd(Nd / Dd)= Id + Nd / Dd =(Id + 1) - (Dd-Nd)/ Dd,其中Id,Nd和Dd为整数,Nd / Dd <1。 Id,Nd和Dd用于创建最终分母除数。 最后,IO,最终的分子除数和最终的分母除数用于创建最终的除数。
摘要:
A system and method are provided for matching a signal (compClk) to a particular frequency band in a multiband communications device. The method accepts a compClk signal, a frequency source is selected from sources collectively covering a range of frequency bands, and a reference clock is supplied from the selected source. If the frequency of the compClk is greater than the reference clock frequency, a high frequency window sampler supplies a first frequency pattern detector output signal (fpdOut—1). Simultaneously, a low frequency window sampler compares the compClk signal with the reference clock. If the frequency of the compClk is less than the reference clock frequency, the low frequency window sampler supplies a second frequency pattern detector output signal (fpdOut—2). The selected frequency source is compared to fpdOut—1 and fpdOut—2 signals, and a determination is made as to whether the selected frequency source coarsely matches the compClk frequency.
摘要:
A method is provided for synthesizing signal frequencies using low resolution rational division. A reference frequency value and synthesized frequency value are accepted. In response to dividing the synthesized frequency value by the reference frequency value, an integer value numerator (n) and an integer value denominator (d) are determined, with n/d=I(N/D)=I+N/D=(I+1)−(D−N)/D), and where N/D
摘要翻译:提供了一种使用低分辨率合理除法合成信号频率的方法。 参考频率值和合成频率值被接受。 响应于将合成频率值除以参考频率值,确定整数值分子(n)和整数分母(d),其中n / d = I(N / D)= I + N / D = (I + 1) - (D-N)/ D),其中N / D <1。 累加器产生(D-N)和来自前一个循环的计数的和,并产生和和分母之间的差异。 将总和与分母进行比较,并产生第一进位位。 第一进位位的补码被加到第一个二进制序列中,第一个二进制序列用于产生一个k位的商。 从(I + 1)中减去k位商以产生除数。
摘要:
A system and method are provided for generating a jitter-attenuated clock using an asynchronous gapped clock source. The method accepts a first reference clock having a first frequency. Using the first reference clock, an asynchronous gapped clock is generated having an average second frequency less than the first frequency. A dynamic numerator (DN) and dynamic denominator (DD) are iteratively calculated for the gapped clock. Then, DN and DD are averaged. In response to the averaging, an averaged numerator (AN) and an averaged denominator (AD) are generated. Finally, the first frequency (first reference clock) is multiplied by the ratio of AN/AD to create a jitter-attenuated second clock having the second frequency.
摘要:
A window sampling system and method are provided for comparing a signal with an unknown frequency to a reference clock. A pattern modulator accepts a compClk signal and supplies a test window with a period equal to n compClk periods, where n is an integer greater than 1. A pattern detector accepts the test window and a reference clock, and contrasts the test window with the reference clock. In response to failing to fit n reference clock periods inside the test window, the pattern detector supplies a frequency pattern detector output signal (fpdOut) indicating that the frequency of the compClk is greater than the reference clock frequency.