阅读说明：本技术 用于分析处理超声信号的方法和设备、超声测量系统和工作设备 (Method and device for evaluating ultrasound signals, ultrasound measuring system and operating device ) 是由 A·文茨勒 M·布罗克曼 于 2019-01-11 设计创作，主要内容包括：本发明涉及一种用于分析处理超声信号的方法(T),在所述方法中,对模拟超声接收信号(E)进行模数转换(T3),并且为了推导用于评估所述超声接收信号(E)的包络曲线(Eh)以数字形式对所述模拟超声接收信号进行信号匹配的滤波过程(T7),其中,在所述滤波过程(T7)之前,复数混频(T4)所述经模数转换的超声接收信号(Ed1),并且以复数的形式执行信号匹配的滤波过程(T7)。(The invention relates to a method (T) for evaluating an ultrasound signal, in which an analog ultrasound receive signal (E) is analog-to-digital converted (T3) and a filter process (T7) for signal matching the analog ultrasound receive signal in digital form is carried out for deriving an envelope curve (Eh) for evaluating the ultrasound receive signal (E), wherein the analog-to-digital converted ultrasound receive signal (Ed1) is complex-mixed (T4) and the signal matched filter process (T7) is carried out in complex form before the filter process (T7).)

1. A method (T) for the evaluation of ultrasound signals,

In the method, an analog-to-digital conversion (T3) is carried out on an analog ultrasound receive signal (E), and the analog ultrasound receive signal is subjected to a signal-matched filter process (T7) in digital form in order to derive an envelope curve (Eh) for evaluating the ultrasound receive signal (E),

wherein:

-complex mixing (T4) the analog-to-digital converted ultrasound receive signal (Ed1) prior to the filtering process (T7),

-performing a filtering process of signal matching in complex form (T7).

2. The method (T) according to claim 1, in which method,

-complex mixing (T4) the analog-to-digital converted ultrasound receive signal (Ed1) with a mixing signal having a mixing frequency,

-the mixing frequency corresponds to a center frequency of a reception frequency band on which the analog ultrasound reception signal (E) is based.

3. Method (T) according to any one of the preceding claims,

in the method, a scan rate is reduced (T6) compared to a scan rate of the analog-to-digital conversion (T3) prior to signal matched complex filtering (T7) of the analog-to-digital converted ultrasound receive signal (Ed1) or a digital ultrasound receive signal (Ed2) derived from the analog-to-digital converted ultrasound receive signal.

4. Method (T) according to any one of the preceding claims,

in the method, the analog-to-digital converted ultrasound receive signal (Ed1) is low-pass filtered (T5) for band limiting before the reduction of the scan rate (T6).

5. Method (T) according to any one of the preceding claims,

in the method, for deriving the envelope curve (Eh), an absolute value formation (D8) of a digital ultrasound receive signal (Edfin) signal-matched filtered in complex form is carried out.

6. The method (T) according to any one of the preceding claims, having the steps of:

-providing (T2) an analog ultrasound receive signal (E) corresponding to the ultrasound transmit signal (S) in a receive frequency band,

-analog-to-digital converting (T3) the ultrasound receive signal (E) by scanning with an input scanning frequency, thereby obtaining (T3') a primary digital ultrasound receive signal (Ed1),

-complex mixing (T4) the primary digital ultrasound receive signal (Ed1) with a mixing signal having a mixing frequency, the mixing frequency corresponding in particular to the center frequency of the receive frequency band, thereby obtaining (T4') a complex secondary digital ultrasound receive signal (Ed2) having a frequency band shifted towards lower frequencies,

-low-pass filtering (T5) for band limiting and reducing (T6) the scan rate at the secondary digital ultrasound receive signal (Ed2), thereby obtaining (T6') a final digital ultrasound receive signal (Edfin),

-signal-matched complex filtering (T7) of the final digital ultrasound receive signal (Edf) with respect to the ultrasound transmit signal (S), thereby obtaining (T7') a signal-matched filtered digital ultrasound receive signal (Edf),

-performing absolute value forming (T8) on the signal-matched filtered digital ultrasound receive signal (Edf), thereby obtaining (T8') an envelope curve (Eh) with respect to the ultrasound receive signal (E),

-evaluating (T9) the envelope curve (Eh) and in particular providing (T10) a list of maxima of position and amplitude of the envelope curve (Eh) and/or providing a list of directions and distances of respective targets.

7. The method of claim 6, wherein the first and second light sources are selected from the group consisting of,

in the method, the provision (T2) of the analog ultrasound receive signal (E) has an ultrasound measurement process and/or a reading from a measured value memory.

8. An apparatus (100) for the analytical processing of ultrasound signals,

the device is provided for, in particular based on the method according to one of claims 1 to 7,

-analog-to-digital converting (T3) the analog ultrasound receive signal (E),

-subjecting the analog-to-digital converted ultrasonic receive signal (Ed1) or a digital ultrasonic receive signal (Ed2, Edfin) derived from the analog-to-digital converted ultrasonic receive signal to a signal matched filtering process (T7) in digital form for deriving an envelope curve (Eh) for evaluating the ultrasonic receive signal (E),

-complex mixing (T4) the analog-to-digital converted ultrasound receive signal (Ed1) before the filtering process (T7), and

-performing said signal matched filtering process in complex form, in particular based on a complex signal matched filter (T7).

9. An ultrasonic measuring system, which is provided for,

-generating and transmitting an ultrasound transmission signal (S),

-receiving an ultrasound receive signal (E) corresponding to the ultrasound transmit signal,

-analytically processing the received ultrasound receive signal (E) by means of the method according to any one of claims 1 to 7 and/or by means of the device according to claim 8.

10. The ultrasonic measuring system according to claim 9, configured as or as part of a driving assistance system or a running assistance system of a working apparatus or a vehicle.

11. A working apparatus or a vehicle having:

-an instrument and/or a driver for driving the instrument,

-control means for controlling the operation of the instrument and/or the driver,

the ultrasound measurement system of any of claims 9 or 10, wherein the control means is coupleable with the ultrasound measurement system and is arranged for controlling the instrument and/or the driver based on the analytically processed ultrasound signal.

Technical Field

The invention relates to a method and a device for evaluating ultrasound signals, an ultrasound measuring system and a working device. The invention relates in particular to a driving assistance system and a driving assistance system for a work apparatus or for a vehicle, and to a work apparatus or a vehicle itself.

Background

Ultrasonic measuring systems are increasingly used in operating devices or vehicles in conjunction with operation assistance systems and in particular with driver assistance systems in order to control the operation of the respective instrument, for example a drive, on the basis of the ultrasonic signals to be evaluated.

By means of the ultrasonic signals to be evaluated, in particular the environmental conditions of the operating device (in particular of the vehicle) can be evaluated. A problem of conventional ultrasonic measuring systems and the corresponding methods for the evaluation of ultrasonic signals is that a large amount of computing effort is usually required for the evaluation, which is manifested in particular by a correspondingly high space requirement and performance requirement for the implementation and execution of the corresponding operations.

Disclosure of Invention

In contrast, the method according to the invention for evaluating an ultrasound signal having the features of claim 1 has the following advantages: the operating effort and therefore the instrumentation effort in terms of area requirement and electrical power for the individual working processes are reduced. According to the invention, this is achieved by means of the features of claim 1: a method for evaluating an ultrasound signal is proposed, in which analog-to-digital conversion is carried out on an analog ultrasound receive signal and the ultrasound receive signal is subjected to a signal-matched filter process in digital form in order to derive an envelope curve for evaluating the ultrasound receive signal, wherein, according to the invention, the analog-to-digital converted ultrasound receive signal or the digital ultrasound receive signal derived therefrom is complex-mixed (komplex mischen) before the filter process and the signal-matched filter process is carried out in a complex manner. By complex mixing, the signal band of the received ultrasound signal can be moved within an appropriate range for more efficient digital processing, thereby creating the possibility of saving space and power in the components used, based on the computational effort that can be reduced.

The dependent claims show preferred embodiments of the invention.

In a preferred embodiment of the method according to the invention, the analog-to-digital-converted ultrasound receive signal is complex-mixed with a mixing signal having a mixing frequency, wherein the mixing frequency corresponds to a center frequency of a receive frequency band on which the analog ultrasound receive signal is based.

In a further preferred embodiment of the method according to the invention, the scan rate is reduced compared to the scan rate of the analog-to-digital conversion before the signal-matched complex filtering of the analog-to-digital converted ultrasound receive signal or of a digital ultrasound receive signal derived from the ultrasound receive signal.

This can be done, for example, by means of a certain factor N and/or the sweep frequency f1/N can be implemented starting from the analog-to-digital conversion sweep frequency f1 on which it is based.

Here, the original based scanning frequency f1 may be in the range up to several hundred kHz and/or the reduction factor may be in the range of 4 to 64.

According to a further advantageous embodiment of the method according to the invention, a further simplification of the signal structure for the evaluation is achieved if the analog-to-digital-converted ultrasound receive signal is low-pass filtered for band limiting before the scan rate is reduced.

By these measures, the data range for describing the ultrasound receive signal is reduced overall.

On the basis of complex-valued processing of the ultrasound receive signals, a particularly simple possibility is obtained for deriving an envelope curve for evaluation.

According to a further advantageous embodiment of the method according to the invention, it is provided that the complex-form signal-matched filtered digital ultrasound receive signal is subjected to absolute value forming in order to derive the envelope curve.

A complete embodiment of the method according to the invention for the evaluation of ultrasound signals (possibly also) has the following steps:

-providing an analog ultrasound receive signal corresponding to the ultrasound transmit signal in a receive frequency band,

-analog-to-digital converting the ultrasound receive signal, including scanning at an input scanning frequency, and thereby obtaining a primary digital ultrasound receive signal,

complex mixing the primary digital ultrasound receive signal with a mixing signal having a mixing frequency which in particular corresponds to the center frequency of the receive frequency band, thereby obtaining a complex secondary digital ultrasound receive signal having a frequency band shifted towards lower frequencies,

-low-pass filtering for band limiting and reducing the scan rate of the secondary digital ultrasound receive signal and thereby obtaining a final digital ultrasound receive signal,

Performing signal-matched complex filtering of the final digital ultrasound receive signal with respect to the ultrasound transmit signal and thereby obtaining a signal-matched filtered digital ultrasound receive signal,

absolute value forming on the signal-matched filtered digital ultrasound receive signal and thereby obtaining an envelope curve with respect to the ultrasound receive signal,

-evaluating the envelope curve and in particular providing a list of maxima of the position and amplitude of the envelope curve and/or providing a list of directions and distances of the respective targets.

The analog ultrasound receive signal may originate from an ultrasound measurement process and/or from a reading from a measurement value memory. Alternatively, a digital ultrasound receive signal which is supplied and has been analog-to-digital converted may also be supplied as a starting point.

The invention further relates to a device for the evaluation of ultrasound signals.

The device is provided, for example, for carrying out the method according to the invention for the evaluation of ultrasound signals.

The device according to the invention is particularly arranged for,

-analog-to-digital converting the analog ultrasound receive signal,

for deriving an envelope curve for evaluating the ultrasound receive signal, subjecting the analog-to-digital converted ultrasound receive signal or a digital ultrasound receive signal derived from the ultrasound receive signal to a filtering process of signal matching in digital form,

Complex mixing the analog-to-digital converted ultrasound receive signal prior to the filtering process,

-performing a filtering process in a complex manner, in particular signal matching based on a complex signal matched filter.

The invention also relates to an ultrasonic measuring system which is provided for generating and transmitting an ultrasonic transmit signal, for receiving an ultrasonic receive signal corresponding to the ultrasonic transmit signal, and for evaluating the received ultrasonic receive signal by means of the method according to the invention and/or by means of a device for evaluating the ultrasonic signal.

Advantageously, the ultrasonic measuring system according to the invention is designed as a driving assistance system or as a driving assistance system of a work apparatus or vehicle, or as a part thereof.

According to a further aspect of the invention, a working device, in particular a vehicle, is also realized.

According to the invention, the working devices are designed with an instrument and/or a drive, a control device for controlling the operation of the instrument and/or the drive, and with an ultrasonic measuring system according to the invention.

The control device can be configured to be coupled to the ultrasound measuring system and is provided for controlling the instrument, in particular the driver, on the basis of the evaluated ultrasound signal.

Drawings

Embodiments of the present invention are described in detail with reference to the accompanying drawings.

Fig. 1 and 3 schematically illustrate, in a block diagram or flowchart, a method of signal processing for determining an envelope curve, on which the invention is based;

fig. 2 and 4 schematically illustrate an embodiment of a method of signal processing for determining an envelope curve according to the invention in the form of a block diagram or a flow chart.

Fig. 5 shows a further embodiment of the method according to the invention for the evaluation of ultrasound signals in the form of a flow chart.

Detailed Description

Embodiments and technical background of the present invention are described in detail below with reference to fig. 1 to 5. Elements and components that are identical or equivalent and that are identical or equivalent are denoted by the same reference numerals. A detailed description of the labeled elements and components is not given in every case where they occur.

The features shown and other characteristics may be isolated from each other in any form and may be combined with each other arbitrarily, as required, without departing from the core of the invention.

Fig. 1 and 3 schematically illustrate, in a block diagram or flowchart, a method U and a device 100' for signal processing for determining an envelope curve, on which the invention is based. They will be referred to as the conventional method U and the conventional apparatus 100' below.

In connection with the first step U1 or first unit, an ultrasonic transmit signal S (e.g. in the form of a transmit pulse) is generated and emitted.

In connection with a subsequent step U2 or a subsequent second unit, an ultrasonic receive signal E (for example in the form of a receive pulse) is received and then in a third step U3 or in connection with a third unit, it is analog-to-digital converted in a scanned manner at a scanning frequency f1, which may lie, for example, in the range of a few hundred kHz, so that a digitized ultrasonic receive signal Ed' in the conventional form is present.

Then, a step U7 or a corresponding unit for signal-matched filtering follows, wherein the parameters which are decisive for the ultrasound transmit signal S are transmitted to the optimum filter, said parameters being based on the step U7 and the corresponding unit.

In a subsequent step U8 and corresponding unit, the result Edf 'of the signal-matched filtering process U7 is processed by low-pass filtering for extracting the conventional envelope curve Eh'.

Fig. 2 and 4 schematically illustrate, in a block diagram or flowchart, an embodiment of a method T of signal processing for determining an envelope curve Eh according to the invention.

The method T according to the invention and the corresponding device 100 for evaluating an ultrasound signal E are based on the following methods:

After the generation and transmission of the T1 ultrasonic transmit signal S, a corresponding provision T2 of the ultrasonic receive signal E and an analog-to-digital conversion T3 of this ultrasonic receive signal are carried out and thus a transition from an analog signal mode to a digital signal mode is carried out.

In a subsequent step T4 of the method T and the corresponding unit of the device 100, the primary continuous digital ultrasound receive signal Ed1 is subjected to a complex mixing which is newly added according to the invention. By this procedure, the secondary digital ultrasonic reception signal Ed2 is obtained in step T4' of the method T and the corresponding unit of the apparatus 100.

The final digital ultrasound receive signal Edfin is obtained in step T6 'by low-pass filtering T5 for band limiting and reduction of scan rate T6, which is then supplied to a complex signal-matched filtering T7 according to the invention, so that a complex signal-matched filtered digital ultrasound receive signal Edf is obtained in step T7'.

In a subsequent step T8, the complex-valued, signal-matched filtered digital ultrasound receive signal Edf is absolute-valued formed, so that in a subsequent step T8', an envelope curve Eh is obtained for the ultrasound receive signal E for further processing.

The following comparison of the method according to the invention according to fig. 2 and 4 with the conventional method according to fig. 1 and 3 results.

In the conventional method with the original scanning rate f1 and a time window tE approximately corresponding to the signal width of the transmitted signal, the efficiency of the optimal filter U7 on which the signal matching is based is determined

I_FIR＝tE·f1 (1)

In this conventional case, a variable R representing the required computing power is derived

R＝I_FIR·f1＝tE·f1²(2)

Since the division of the scanning frequency of the original scanning frequency f1 by a factor N is taken into account after the low-pass filtering in the method according to the invention, the following relation (3) applies in particular

f1 ═ f1/N and I_FIR′＝tE·f1^′＝tE·f1/N (3)

According to the invention, in the case of identical time windows tE, the following relation (4) is obtained for the variable R' representing the required calculation power

R′＝4·f1/N·tE·f1/N＝4·R/N²

This means that the required computational power R' is proportional to the scan frequency or the square of the 1/N reduction in scan rate.

Fig. 5 shows, in the form of a flow chart, an embodiment of the method T for evaluating an ultrasonic received signal E according to the invention or of the corresponding device 100 described in conjunction with fig. 2 and 4. Here, the steps and cells T1 through T8' remain the core.