A method and a system for generating multi-frequency pulsed signals

Abstract

A method for generating multi-frequency pulsed signals (S) using a pulse generator (2), wherein said method comprises the step of correcting a phase offset in said pulsed signals (S) using a processing unit (3) configured to evaluate a time deviation of said pulsed signals (S) from at least one time-stamped reference signal (R), wherein the method comprises the step of operating the pulse generator (2) in at least two operational modes, wherein in a first operational mode the pulse generator (2) generates pulsed signals having a first predefined frequency range, and in a second operational mode the pulse generator (2) generates pulsed signals having a second predefined frequency range, wherein the second frequency range is wider than the first frequency range. It is also disclosed a system for generating multi-frequency pulsed signals (S) operable using said method.

Description

[0001] A method and a system for generating multi- frequency pulsed signals

[0002] The invention relates to a method and a system for generating multi- frequency pulsed signals .

[0003] Accurate pulse generators , also known as frequency or clock generators , produce stable and precise clock signals that serve as a time reference for other system components . These generators are crucial in applications where even minor frequency dri fts can cause data misalignment , timing errors , or degraded performance . In fact , they are used to achieve the performance of atomic clocks which are often very expensive . In a GNSS-based system ( Global Navigation Satellite System) , such a module is often synchroni zed to the highly accurate time reference derived from satellite time-stamped reference signals , ensuring the generated clocks and pulses remain aligned with global time standards . This synchroni zation is typically achieved through feedback mechanisms where the frequency generator adj usts its internal oscillators or accumulators based on said time-stamped reference signals .

[0004] Designing an accurate frequency generator is challenging due to the imperfections of practical oscillators . Frequency dri ft is one of the primary concerns , as the output frequency of an oscillator can vary over time due to temperature fluctuations , supply voltage variations , component aging, or mechanical stress , leading to deviations from the desired frequency . Jitter, which refers to short-term timing variations or inconsistencies between successive pulses , introduces additional uncertainty that can degrade synchroni zation and precision, especially in high-frequency or long-duration applications . Over time , even small amounts of dri ft or accumulated j itter can result in signi ficant timing errors , causing misalignment with other system components or reference signals. To achieve high accuracy, frequency generators must employ compensation techniques, such as feedback loops, fractional period adjustments, or external time references, to correct these variations and maintain stable, predictable output signals .

[0005] The prior art in [1] focuses on fine-grained clock resolution by combining low-frequency and high-frequency clock sources, activating the latter only when needed to minimize power consumption. In [2] , an ADPLL-based frequency synthesizer for providing a reference clock signal is provided. The limitation of the methods in [1] and [2] is that they do not synchronize the generated clock with a reference time, which makes them less accurate. In [3] , a high-precision time-frequency reference source for navigation enhancement systems is disclosed, combining a crystal oscillator with a 48-bit direct digital frequency synthesis (DDS) to generate stable reference signals (10.23MHz and 62MHz) for both transmitting and receiving units. The limitation of such system is that the frequency of the reference signals and the DDS bit width are held constant.

[0006] It is an object of the invention to correct the short-comings of the prior art and to provide a solution for generating multifrequency pulsed signals featuring minimized power consumption for the output pulses while maintaining configurability and high resolution. This and other objects which will become apparent from the following disclosure, are provided with a method and a system having the features of one or more of the appended claims.

[0007] In a first aspect of the invention, the method for generating multi-frequency pulsed signals using a pulse generator comprises the step of correcting a phase offset in said pulsed signals using a processing unit configured to evaluate a time deviation of said pulsed signals from at least one time-stamped reference signal, wherein the method comprises the step of operating the pulse generator in at least two operational modes , wherein in a first operational mode the pul se generator generates pulsed signals having a first predefined frequency range , and in a second operational mode the pulse generator generates pulsed signals having a second predefined frequency range, wherein the second frequency range is wider than the first frequency range . The first operational mode requires relatively simple architecture and features higher pulse accuracy than the second operational mode because in the first operational mode , the errors of every pulse are calculated and compensated . In the current context , pulse accuracy describes how closely a generated or detected pulse matches its intended characteristics in time , amplitude , and shape . It ' s essentially a measure of how "true" the pul se is to its design . The second operational mode requires relatively more complex architecture and features lower pulse accuracy but supports a higher frequency range . Generating the lower frequency pulsed signals with the first operational mode and generating the higher frequency pulsed signal with the second operational mode , leads to the support of higher frequency ranges without much sacrifice on pulse accuracy . Additionally, by using the proces sing unit to estimate and correct the phase of fset the silicon area is reduced and the application flexibility is increased .

[0008] Advantageously, the method may comprise the step of setting the first frequency range between 0 . 1 Hz and 1 kHz and the second frequency range between 10 Hz and 10 MHz .

[0009] More advantageously, the step of evaluating a time deviation of said pulsed signals from at least one time-stamped reference signal may comprise evaluating a time deviation of a rising edge and / or a falling edge of said pulsed signals from said at least one time-stamped reference signal .

[0010] To increase the configurability, the method may comprise the steps of providing a frequency clock module for clocking the pulse generator and adj usting the frequency range of the pulsed signal generated by the pulse generator by adj usting a clock rate of the frequency clock module and / or by selecting a bit width of a register and / or by selecting a bit width of an intermediate node in said pulse generator .

[0011] The method may comprise the steps of : providing at least three frequency clocks in the frequency clock module ; configuring the second frequency clock to be multiple times faster than the first frequency clock; clocking the pulse generator by the first and by the second frequency clocks ; and clocking the processing unit by the third frequency clock .

[0012] The method may comprise the steps of : determining the time of a rising edge and / or the time of a falling edge of said pulsed signals using an input counter clocked by the first frequency clock; estimating a phase of fset in the pulsed signals by using the processing unit for evaluating a time deviation of said pulsed signals from time-stamped reference signals ; and feeding said phase of fset to the pulse generator for adj usting the time of a rising edge and / or the time of a falling edge of the pulsed signals , wherein the phase of fset is added to said time of a rising edge and / or to said time of a falling edge .

[0013] The method may comprise the step of applying fine timing to rising edges and / or to falling edges of the pulsed signals using a fractional period accumulator clocked by the second frequency clock . Fine timing, i . e . fractional-delay filtering, precisely delays a signal by a non-integer number of samples , or the highly precise measurement of event timing . Fine timing is used to delay a signal by a fraction of a sampling period, which is useful for synchroni zing signals , implementing precise filters , or creating speci fic delays in audio and digital communications .

[0014] The method may comprise the steps of : estimating the phase of fset for every pulse of said pulsed signals when the pulse generator is in the first operational mode ; and estimating the phase of fset periodically over N pulses within the pulsed signals , wherein N is a predef ined integer value , when the pulse generator is in the second operational mode . The integer N may be user-defined and adj usted according to the desired power consumption and pulse accuracy .

[0015] The method may comprise the steps of : using at least one input counter for determining a time of every ri sing edge and / or every fal ling edge of the pul sed signals when the pulse generator is in the first operational mode ; and using the at least one input counter for determining a time of an initial rising edge and / or a time of an initial falling edge in the pulsed signals when the pulse generator is in the second operational mode . The initial pulse period is typically provided by the user .

[0016] The at least one counter is typically used to count the number of pulses . This number may be required by the pulse generator when it is operating in the second operational mode where the number N of pulses is relevant .

[0017] Suitably, the method may comprise the step of operating the pulse generator in the first operational mode , wherein the method comprises the steps of : generating pulsed signals based on a first predefined pulse width and on the time of every rising edge or on the time of every falling edge of said pulsed signals ; and us ing the process ing unit for adj usting the time of every rising edge or the time of every fall ing edge by adding the phase of fset to said time of every ri sing edge or to said time of every falling edge ; and generating pulsed signals based on the adj usted time of every rising edge or the adj usted time of every falling edge .

[0018] More suitably, the method may comprise the step of operating the pulse generator in the second operational mode , wherein the method comprises the steps of : providing a time of an initial rising edge or a time of an initial falling edge of the pulsed signals ; generating pulsed signals by determining times of subsequent rising edges and times of subsequent fall ing edges of the pulsed signals based on said time of the initial rising edge or on said time of the initial falling edge and on a predefined pulse period; adj usting the time of the initial ris ing edge or the time of the initial falling edge after every N pulses by adding the phase of fset to said time of the initial rising edge or to said time of the initial falling edge ; and generating pulsed signals using the adj usted time of the initial rising edge or the adj usted time of the initial falling edge . Optionally, the method may comprise the step of generating pulsed signals by determining times of subsequent rising edges and times of subsequent fall ing edges of the pulsed signals based on said time of the initial rising edge or on said time of the initial falling edge and on a predefined pulse period and on a second predefined pulse width .

[0019] In a second aspect o f the invention, the system for generating multi- frequency pulsed signals comprises a processing unit for estimating a phase error in the pulsed signal s by evaluating a time deviation of said pulsed signals from time-stamped reference signals , wherein the system comprises a pulse generator configured to operate in at least two operational modes , wherein in a first operational mode the pulse generator is configured to generate pulsed signals having a first predefined frequency range , and in a second operational mode the pulse generator is configured to generate pulsed signals having a second predefined frequency range , wherein the second frequency range is wider than the first frequency range .

[0020] The first operational mode requires relatively simple architecture and features higher pulse accuracy than the second operational mode because in the first operational mode , the errors of every pulse are calculated and compensated . The second operational mode requires relatively more complex architecture and features lower pul se accuracy but supports a higher frequency range . Generating the lower frequency pulsed signals with the first operational mode and generating the higher frequency pulsed signal with the second operational mode , leads to the support of higher frequency ranges without much sacri fice on pulse accuracy . Additionally, by using the processing unit to estimate and correct the phase of fset the silicon area is reduced and the application flexibility is increased .

[0021] Advantageously, the system may comprise a frequency clock module for clocking the pulse generator and for clocking the processing unit .

[0022] More advantageously, the frequency clock module may comprise at least three frequency clocks , wherein the pulse generator is configured to be clocked by the first and by the second frequency clocks , and wherein the processing unit is configured to be clocked by the third frequency clock .

[0023] Even more advantageously, the second frequency clock is configured to be multiple times faster than the first frequency clock . The higher frequency clock provides the benefits of higher pulse accuracy while the lower frequency clock provides the benefit of lower power consumption .

[0024] Advantageously, the system may comprise at least one counter configured for timing rising edges and / or falling edges of said pulsed signal .

[0025] Suitably, the system comprises a fractional period accumulator clocked by the second frequency clock for applying f ine timing to rising edges and / or falling edges of the pulsed signals .

[0026] More suitably, the pulse generator is configured to estimate the phase of fset for every pulse of the pulsed signals when the pulse generator is in the first operational mode , and the pulse generator is configured to estimate the phase of fset periodically over N pulses within the pulsed signals , wherein N is a predefined integer value , when the pulse generator is in the second operational mode .

[0027] The invention will hereinafter be further elucidated with reference to the drawing of an exemplary embodiment of a system and a method according to the invention that is not limiting as to the appended claims .

[0028] In the drawing : figure 1 shows a schematic of an exemplary system according to the invention; figure 2 shows a schematic of an exemplary pulse generator according to the invention; figure 3 shows a graphical representation of exemplary pulse signals when the pulse generator of the invention in the first operational mode ; and figure 4 shows a graphical representation of exemplary pulse signals when the pulse generator of the invention in the second operational mode .

[0029] Whenever in the figures the same reference numerals are applied, these numerals refer to the same parts .

[0030] This invention relates to a method and a system for accurately generating multi- frequency pulsed signals in a speci fic predefined frequency range given the desired pulse characteristics . The pulsed signals may optionally be in the form of rectangular pulses . Typically, the parameter pulse width indicates the duration of the active state of each pulse , and the parameter period is the duration o f one pulse which is the time di f ference between two successive rising ( or falling) edges . This parameter is typically calculated based on the frequency of the clock used for generating the pulse .

[0031] The system 1 and the method of the invention are designed to produce pulsed s ignals S within a frequency range configurable by the user . The system 1 and the method may be suitably designed to feature optimum power consumption for the frequency range of 0 . 1 Hz to 10 MHz . However, the design' s flexibility allows for generating much higher frequencies by increasing the registers ' bit width ( increas ing power consumption) or reducing the pul se accuracy .

[0032] The system 1 features two frequency generation modes : a first operational mode , optionally covering 0 . 1 Hz to 1 kHz , and a second operational mode , optionally supporting 10 Hz to 10 MHz . The first operational mode employs a simpler hardware method, but the timing of each rising edge must be determined by the processing unit . In contrast , the second operational mode which uses a more complex frequency generation method, requires only the timing of the first ris ing edge and the pulse period to be speci fied; the pulse generator 2 then handles all subsequent rising edges, with the processing unit 3 maintaining accuracy by providing offset feedback to the pulse generator 2.

[0033] The pulse generator 2 can be clocked by a frequency clock module 4 that provides different clock signals 4.1, 4.2, 4.2 while a processing unit 3 can be used for generating regular feedback using the interrupt signal of the pulse generator 2 and a time- stamped reference signal R. The time-stamped reference signal R can be any arbitrary internal or external signal. For example, in a GNSS system, it is possible to use the estimated time using the GNSS signal as the reference signals R which is calculated by the processing unit through the signal received from the antenna. A realization of such setting is shown in figure 1.

[0034] The frequency clock module 4 in figure 1 generates the required clocks 4.1, 4.2 ,4.3 wherein the first 4.1 and the second clocks 4.2 clocks with different frequencies are used to clock the pulse generator 2, and the third clock 4.3 is used to clock the processing unit 3 (e.g., ARM or DSP) . Using the initial load value set by the processing unit 3 and the clocks 4.1, 4.2 ,4.3, the pulse generator outputs a pulse train with the chosen characteristics as well as an interrupt signal for the processing unit 3. The processing unit 3 provides feedback to pulse generator 2 on every interrupt, and the pulse generator 2 adjusts the output pulse S accordingly. A very simplified block diagram of the pulse generator 2 is depicted in figure 2.

[0035] The first and the second operational modes operate based on at least one input counter 5. This at least one counter 5 is based on the first clock 4.1 and is used to determine the coarse timing of rising and / or falling edges of the generated pulsed signals S. The Controller part of the pulse generator 2 has two main objectives: a) determine the coarse timing of rising and falling edges of pulses (riseTrig and fallTrig) and the expected delays (riseDelay and fallDelay) based on the first clock 4.1 according to the desired pulse parameters, and b) count the number of occurred rising (or falling) edges which can be used to request feedback from the processing unit 3 in the second operational mode. The fractional period accumulator 6 i.e. the delay generator, is used for enhancing the pulse accuracy of the output pulses S. In fact, it 6 applies fine timing delays by generating fractional delays using the second frequency clock 4.2.

[0036] Figure 3 illustrates the pulse signals S when the pulse generator 2 is in the first operational mode. In said mode, a rectangular wave is generated using load and width values. The load value defines the time of rise-edge (or fall-edge) of each pulse in terms of the input counter, and the value of width determines the length of the active cycle of each generated pulse. These values can be modified by the processing unit's 3 feedback to change the clock characteristics after every interrupt signal to processing unit 3. In addition, the width parameter can be changed on-the-fly where necessary.

[0037] In Figure 4, the operation of the second operational mode is illustrated. Said mode supports a wider frequency range and higher frequencies up to 10 MHz compared to the first mode. The parameter 'load' is initialized at the startup. After that, the location of rising and falling edges of the generated signals S are determined using width, period, and offset values. As part of the feedback process, the offset is set by the processing unit's 3 feedback and is used for phase correction. The timing of this feedback is determined by the interrupt signal generated at the pulse generator's 2 output. In fact, the used-def ined parameter countDiv decides the number of pulses after which a phase correction is required, and when an internal counter reaches that value, an interrupt signal is generated and indexSamp (the rise-edge or fall-edge of each pulse) is sampled at that time. This technique is used to keep the rate of processor interrupts within the supported bounds, save the processor 3 enough time to execute error estimation algorithms while maintaining the resolutions that a per-pulse interrupt would achieve .

[0038] As mentioned earlier, the phase of fset is calculated by a processing unit 3 such as a CPU or ARM . Of fset (phase error ) estimation in this context refers to evaluating the timing di f ference between the locally generated pulse S and an time- stamped reference R, such as GNSS or BLE . Since local oscillators do not perfectly generate their nominal frequencies and are subj ect to dri ft and j itter, the generated pulses S may not coincide exactly with their expected positions . The of fset is obtained by comparing the actual pulse edge with the ideal position defined by the reference R . This estimation can be performed on every pulse , providing fine-grained correction but requiring higher processing ef fort (used in the first operational mode ) , or at longer intervals ( every-n-pulses ) used in the second operational mode , which reduces interrupt activity and power consumption while averaging out short-term noise . The resulting of fset value indicates the deviation of the local oscillator from the reference R, and can be used to adj ust counters 5 or delay 6 parameters to maintain long-term pulse alignment .

[0039] The method and the system 1 of the invention incorporate two distinct operating modes that di f fer in their frequency ranges , pulse generation mechanisms , and interaction with the processing unit 3 for feedback . A great advantage of using a processing unit 3 for error estimation, as ide from configurabil ity during operation, is that one can easily develop and test di f ferent of fset estimation algorithms without changing the hardware design . This approach also reduces hardware complexity and footprint on the chip .

[0040] Additionally, the method and the system 1 have been optimi zed for power consumption, which may be proved based on measured performance values and comparisons with existing figures in the prior art . It is worth mentioning that while the previously defined frequency ranges are used in the system 1 and the method of the invention, the invention of fers flexibility to extend the supported frequency range by modi fying the register bit widths . This can be achieved at the cost of either increased power consumption or reduced pulse accuracy ( i . e . , higher ppm values ) .

[0041] The invention may be applicable in many fields . In GNSS receivers , an accurate frequency generator is critical for maintaining the timing required for satellite signal tracking, correlation, and navigation data decoding . Beyond the receiver itsel f , the generator can provide a time pulse or clock signal to other modules on the board, supporting synchroni zation among various subsystems such as ADCs , DSP blocks , and communication interfaces . As a standalone component , a frequency generator finds wide application in telecommunications , where it can serve as a reference for base stations or network timing protocols . It is also used in test and measurement equipment, smart grids , distributed sensors , and industrial control systems that require synchroni zed operations across multiple devices .

[0042] Although the invention has been discussed in the foregoing with reference to an exemplary embodiment of the method of the invention, the invention is not restricted to this particular embodiment which can be varied in many ways without departing from the invention . The discussed exemplary embodiment shall therefore not be used to construe the append-ed claims strictly in accordance therewith . On the contrary the embodiment is merely intended to explain the wording of the appended claims without intent to limit the claims to this exemplary embodiment . The scope of protection of the invention shall therefore be construed in accordance with the appended claims only, wherein a possible ambiguity in the wording of the claims shall be resolved using this exemplary embodiment.

[0043] References :

[0044] 1. 10620661 B2 - Sep 2023, Sublet, Fine-Grained Clock

[0045] Resolution Using Low and High Frequency Clock Sources in A Low-Power System. 2. 11,573,594 B2 - Feb 2023, 02 / 2023, Norman et all - Methods and Apparatuses for Providing a Reference Clock Signal.

[0046] 3. CN112583404B - High-precision time-frequency reference source of navigation enhancement system - Google Patents. (2020, November 12) https : / / patents .google . com / patent / CN112583404B / en?oq=CN112

[0047] 583404B

Claims

CLAIMS1. A method for generating multi-frequency pulsed signals (S) using a pulse generator (2) , wherein said method comprises the step of correcting a phase offset in said pulsed signals (S) using a processing unit (3) configured to evaluate a time deviation of said pulsed signals (S) from at least one time-stamped reference signal (R) , characterized in that the method comprises the step of operating the pulse generator (2) in at least two operational modes, wherein in a first operational mode the pulse generator (2) generates pulsed signals having a first predefined frequency range, and in a second operational mode the pulse generator (2) generates pulsed signals having a second predefined frequency range, wherein the second frequency range is wider than the first frequency range.

2. The method according to claim 1, characterized in that the method comprises the step of setting the first frequency range between 0.1 Hz and 1 kHz and the second frequency range between 10 Hz and 10 MHz.

3. The method according to claim 1 or 2, characterized in that the step of evaluating a time deviation of said pulsed signals (S) from at least one time-stamped reference signal (R) comprises evaluating a time deviation of a rising edge and / or a falling edge of said pulsed signals (S) from said at least one time-stamped reference signal (R) .

4. The method according to any one of the preceding claims, characterized in that the method comprises the steps of: providing a frequency clock module (4) for clocking the pulse generator (2) ; and adjusting the frequency range of the pulsed signal (S) generated by the pulse generator (2) by adjusting a clock rate of the frequency clock module (4) and / or by selecting a bit width of a register in said pulse generator (2) and / or by selecting a bit width of an intermediate node in said pulse generator (2) .

5. The method according to any one of the preceding claims, characterized in that the method comprises the steps of: providing at least three frequency clocks (4.1, 4.2, 4.3) with the frequency clock module (4) ; configuring the second frequency clock (4.2) to be a predefined multiple times faster than the first frequency clock (4.1) ; clocking the pulse generator (2) by the first (4.1) and by the second (4.2) frequency clocks; and clocking the processing unit (3) by the third frequency clock (4.3) .

6. The method according to any one of the preceding claims, characterized in that the method comprises the steps of: determining the time of a rising edge and / or the time of a falling edge of said pulsed signals (S) using at least one input counter (5) clocked by the first frequency clock; estimating a phase offset in the pulsed signals (S) by using the processing unit (3) for evaluating a time deviation of said pulsed signals (S) from time-stamped reference signals (R) ; and feeding said phase offset as feedback to the pulse generator (2) for adjusting the time of a rising edge and / or the time of a falling edge of the pulsed signals (S) , wherein the phase offset is added to said time of a rising edge and / or to said time of a falling edge.

7. The method according to any one of the preceding claims, characterized in that the method comprises the step of applying fine timing to rising edges and / or to falling edges of the pulsed signals using a fractional period accumulator (6) clocked by the second frequency clock (4.2) .

8. The method according to any one of the preceding claims, characterized in that the method comprises the steps of: estimating the phase offset for every pulse of said pulsed signals (S) when the pulse generator (2) is in the first operational mode; andestimating the phase offset periodically over N pulses within the pulsed signals (S) , wherein N is a predefined integer value, when the pulse generator is in the second operational mode.

9. The method according to any one of the preceding claims, characterized in that the method comprises the steps of: using at least one input counter (5) for determining a time of every rising edge and / or every falling edge of the pulsed signals (S) when the pulse generator (2) is in the first operational mode; and using the at least one input counter (5) for determining a time of an initial rising edge and / or a time of an initial falling edge in the pulsed signals (S) when the pulse generator (2) is in the second operational mode.

10. The method according to any one of the preceding claims, characterized in that the method comprises the step of operating the pulse generator (2) in the first operational mode, wherein the method comprises the steps of: generating pulsed signals based on a first predefined pulse width and on the time of every rising edge or on the time of every falling edge of said pulsed signals (S) ; and using the processing unit for adjusting the time of every rising edge or the time of every falling edge by adding the phase offset to said time of every rising edge or to said time of every falling edge; and generating pulsed signals (S) based on the adjusted time of every rising edge or the adjusted time of every falling edge .

11. The method according to any one of the preceding claims, characterized in that the method comprises the step of operating the pulse generator (2) in the second operational mode, wherein the method comprises the steps of: providing a time of an initial rising edge or a time of an initial falling edge of the pulsed signals (S) ; generating pulsed signals by determining times ofsubsequent rising edges and times of subsequent falling edges of the pulsed signals (S) based on said time of the initial rising edge or on said time of the initial falling edge and on a predefined pulse period; adjusting the time of the initial rising edge or the time of the initial falling edge after every N pulses by adding the phase offset to said time of the initial rising edge or to said time of the initial falling edge; and generating pulsed signals (S) using the adjusted time of the initial rising edge or the adjusted time of the initial falling edge.

12. The method according to claim 11, characterized in that the method comprises the step of generating pulsed signals (S) by determining times of subsequent rising edges and times of subsequent falling edges of the pulsed signals (S) based on said time of the initial rising edge or on said time of the initial falling edge and on a predefined pulse period and on a second predefined pulse width.

13. A system (1) for generating multi-frequency pulsed signals, wherein said system comprises a processing unit (3) for estimating a phase error in the pulsed signals by evaluating a time deviation of said pulsed signals (S) from time-stamped reference signals (R) , characterized in that the system (1) comprises a pulse generator (2) configured to operate in at least two operational modes, wherein in a first operational mode the pulse generator (2) is configured to generate pulsed signals (S) having a first predefined frequency range, and in a second operational mode the pulse generator (2) is configured to generate pulsed signals (S) having a second predefined frequency range, wherein the second frequency range is wider than the first frequency range.

14. The system (1) according to claim 13, characterized in that the system comprises a frequency clock module (4) for clocking the pulse generator (2) and for clocking the processing unit ( 3 ) .

15. The system (1) according to claim 14, characterized in that the frequency clock module (4) comprises at least three frequency clocks (4.1, 4.2, 4.3) , wherein the pulse generator(2) is configured to be clocked by the first (4.1) and by the second (4.2) frequency clocks, and wherein the processing unit(3) is configured to be clocked by the third frequency clock (4.3) .

16. The system (1) according to claim 15, characterized in that the second frequency clock (4.2) is configured to be a predefined multiple of times faster than the first frequency clock (4.1) .

17. The system (1) according to any one of claims 13-16, characterized in that the system (1) comprises at least one counter (5) configured for timing rising edges and / or falling edges of said pulsed signals (S) .

18. The system (1) according to any one of claims 13-17, characterized in that the system (1) comprises a fractional period accumulator (6) clocked by the second frequency clock (4.2) for applying fine timing to rising edges and / or falling edges of the pulsed signals (S) .

19. The system (1) according to any one of claims 13-18, characterized in that the pulse generator (2) is configured to estimate the phase offset for every pulse of the pulsed signals (S) when the pulse generator is in the first operational mode, and the pulse generator (2) is configured to estimate the phase offset periodically over N pulses within the pulsed signals (S) , wherein N is a predefined integer value, when the pulse generator (2) is in the second operational mode.

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