Height measurement method, device and equipment of aircraft and storage medium

Abstract

The invention provides a height measurement method, device and equipment of an aircraft and a storage medium, and relates to the technical field of radio. The method comprises the following steps: controlling a front-end transmitting module to transmit a frequency-modulated continuous wave signal through a radio frequency module; acquiring a first digital echo signal of a receiving channel and a second digital echo signal of a coupling channel, which are acquired by a radio frequency module for echo signals received by a front-end receiving module; according to the height estimated value of the aircraft, a preset constant beat frequency and a preset constant frequency modulation parameter, determining a starting time for frequency mixing dechirp; according to the starting time, performing frequency mixing dechirp processing on the second digital echo signal to obtain a beat signal; and determining the height value of the aircraft in the current measurement period according to the beat signal and the starting time. Therefore, the measurement accuracy and the measurement precision of the height of the aircraft are improved.

Description

Technical Field

[0001] The present invention relates to the field of radio technology, and in particular to a method, device, equipment and storage medium for measuring the altitude of an aircraft. Background Art

[0002] Altimeters can be installed on various aircraft to measure their true height from the ground or water. The basic measurement principle is to obtain a beat signal by mixing the echo with the transmitted signal, and then extract the frequency value of the beat signal through signal processing methods such as FFT to obtain the aircraft's altitude information. Altimeters often use a constant beat frequency system, in which a fixed beat frequency is pre-set in the system. When measuring altitude, the size of the frequency modulation period needs to be continuously adjusted so that the beat frequency after mixing the echo with the transmitted signal is near the preset fixed beat frequency value, and then the aircraft's altitude is calculated by extracting its spectrum frontier value.

[0003] The constant beat frequency altimeter has the advantages of high detection signal-to-noise ratio and strong anti-interference ability of the system, but the system needs to constantly adjust the frequency modulation period of the transmission signal, which greatly increases the complexity of the software setting. In addition, when the required frequency modulation period is too large, two problems will arise: first, the frequency modulation time of the microwave component has an upper limit, and the microwave component cannot modulate the frequency modulation wave with a too long modulation time; second, if the modulation time is too long, the height measurement period will be longer, reducing the working efficiency of the entire system and affecting the refresh rate of the system result output. When the required frequency modulation period is smaller, two problems will also arise. First, the frequency modulation time of the microwave component is too small, and the step value of the frequency modulation wave is too large, which will reduce the accuracy of the system height measurement results; second, if the modulation time is too small, the number of AD sampling points will be too small, which may cause the system height measurement effect to be poor. Summary of the invention

[0004] The object of the present invention is to provide a method, device, equipment and storage medium for measuring the height of an aircraft in order to improve the measurement accuracy and precision of the height of the aircraft, in view of the above-mentioned deficiencies in the prior art.

[0005] To achieve the above purpose, the technical solution adopted in the embodiment of the present application is as follows:

[0006] In a first aspect, an embodiment of the present application provides a method for measuring the altitude of an aircraft, which is applied to a processing module in an altitude measuring device loaded on the aircraft, wherein the altitude measuring device also includes: a radio frequency module, a front-end transmitting module and a front-end receiving module; the method includes: controlling the front-end transmitting module to emit a frequency modulated continuous wave signal through the radio frequency module; obtaining a first digital echo signal of a receiving channel and a second digital echo signal of a coupling channel acquired by the radio frequency module from an echo signal received by the front-end receiving module; determining a starting time for mixing and de-skewing according to an estimated altitude of the aircraft, a preset constant beat frequency and a preset constant frequency modulation parameter; the estimated altitude is the altitude value obtained by the aircraft in the last measurement cycle; performing mixing and de-skewing processing on the first digital echo signal according to the start time and the second digital echo signal to obtain a beat signal; and determining the altitude value of the aircraft in the current measurement cycle according to the beat signal and the start time.

[0007] In one embodiment, the preset constant frequency modulation parameters include: a frequency modulation bandwidth and a frequency modulation period; determining the start time for mixing de-skewing based on the estimated altitude of the aircraft, the preset constant beat frequency, and the preset constant frequency modulation parameters includes: calculating the start time based on the estimated altitude of the aircraft, the preset constant beat frequency, the frequency modulation bandwidth, and the frequency modulation period.

[0008] In one implementation, performing mixing and de-skewing processing on the first digital echo signal according to the start time and the second digital echo signal to obtain a beat signal includes: determining a digital mixing signal of the receiving channel as a first digital mixing signal; performing digital mixing processing on the first digital echo signal using the first digital mixing signal to obtain a first target digital mixing signal of the receiving channel; generating a digital mixing signal of the coupling channel according to the start time as a second digital mixing signal; performing digital mixing processing on the first digital echo signal using the second digital mixing signal to obtain a second target digital mixing signal of the coupling channel; and performing mixing and de-skewing processing on the first target digital mixing signal using the second target digital mixing signal to obtain the beat signal.

[0009] In one embodiment, determining the altitude value of the aircraft in the current measurement period based on the beat signal and the start time includes: performing frequency domain transformation on the beat signal to obtain a spectrum signal of the beat signal; performing spectrum front detection on the spectrum signal to obtain target spectrum parameters of the beat signal; and calculating the altitude value of the aircraft in the current measurement period based on the target spectrum parameters and the start time.

[0010] In one implementation, performing frequency domain transformation on the beat signal to obtain the spectrum signal of the beat signal includes: performing differentiation processing on the phase of the beat signal to obtain the instantaneous frequency signal of the beat signal as the spectrum signal.

[0011] In one embodiment, calculating the altitude value of the aircraft in the current measurement period based on the target spectrum parameters and the start time includes: calculating the altitude value of the aircraft in the current measurement period based on the target spectrum parameters, the preset constant frequency modulation parameters and the start time.

[0012] In one embodiment, the preset constant frequency modulation parameters include: frequency modulation bandwidth and frequency modulation period; the calculation of the altitude value of the aircraft in the current measurement period based on the target spectrum parameters, the preset constant frequency modulation parameters and the start time includes: calculating the frequency modulation slope based on the frequency modulation bandwidth and the frequency modulation period; calculating the altitude value of the aircraft in the current measurement period based on the target spectrum parameters, the frequency modulation slope and the start time.

[0013] In a second aspect, an embodiment of the present application also provides an aircraft altitude measurement device, comprising: a transmitting module, configured to control a front-end transmitting module to emit a frequency modulated continuous wave signal through a radio frequency module; a receiving module, configured to obtain a first digital echo signal of a receiving channel and a second digital echo signal of a coupling channel acquired by the radio frequency module from an echo signal received by the front-end receiving module; a determining module, configured to determine a starting time for mixing and de-skewing according to an estimated altitude of the aircraft, a preset constant beat frequency, and a preset constant frequency modulation parameter; the estimated altitude is the altitude value obtained by the aircraft in the previous measurement cycle; according to the start time and the second digital echo signal, mixing and de-skewing the first digital echo signal to obtain a beat signal; according to the beat signal and the start time, determining the altitude value of the aircraft in the current measurement cycle.

[0014] In one embodiment, the preset constant frequency modulation parameters include: frequency modulation bandwidth and frequency modulation period; the determination module is configured to calculate the start time based on the estimated altitude of the aircraft, the preset constant beat frequency, the frequency modulation bandwidth and the frequency modulation period.

[0015] In one embodiment, the determination module is configured to: determine the digital mixing signal of the receiving channel as the first digital mixing signal; use the first digital mixing signal to perform digital mixing processing on the first digital echo signal to obtain a first target digital mixing signal of the receiving channel; generate the digital mixing signal of the coupling channel as the second digital mixing signal according to the start time; use the second digital mixing signal to perform digital mixing processing on the first digital echo signal to obtain a second target digital mixing signal of the coupling channel; use the second target digital mixing signal to perform mixing de-skew processing on the first target digital mixing signal to obtain the beat signal.

[0016] In one embodiment, the determination module is configured to: perform frequency domain transformation on the beat signal to obtain a spectrum signal of the beat signal; perform spectrum front detection on the spectrum signal to obtain target spectrum parameters of the beat signal; and calculate the altitude value of the aircraft in the current measurement period based on the target spectrum parameters and the start time.

[0017] In one implementation, the determination module is configured to: perform differentiation processing on the phase of the beat signal to obtain an instantaneous frequency signal of the beat signal as the spectrum signal.

[0018] In one implementation, the determination module is configured to calculate the altitude value of the aircraft in the current measurement period according to the target spectrum parameter, the preset constant frequency modulation parameter and the start time.

[0019] In one embodiment, the preset constant frequency modulation parameters include: frequency modulation bandwidth and frequency modulation period; the determination module is configured to: calculate the frequency modulation slope according to the frequency modulation bandwidth and the frequency modulation period; calculate the altitude value of the aircraft in the current measurement period according to the target spectrum parameters, the frequency modulation slope and the start time.

[0020] In a third aspect, an embodiment of the present application further provides a height measurement device, including: a processing module, a radio frequency module, a front-end transmitting module, a front-end receiving module and a storage medium, wherein the processing module is connected to the radio frequency module, and the radio frequency module is respectively connected to the front-end transmitting module and the front-end receiving module;

[0021] The storage medium stores program instructions executable by the processing module. When the height measuring device is running, the processing module communicates with the storage medium via a bus, and the processing module executes the program instructions to perform the steps of any one of the above methods.

[0022] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of any one of the above methods are executed.

[0023] The beneficial effects of the present application are as follows: while maintaining a preset constant beat frequency and a preset constant frequency modulation parameter, by determining the starting time for mixing and de-skewing, then generating a digital mixing signal based on the starting time to perform mixing and de-skewing processing on the second digital echo signal, and then determining the altitude value of the current measurement cycle of the aircraft based on the starting time, thereby improving the measurement accuracy and precision of the aircraft altitude. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic diagram of a flow chart of a method for measuring the altitude of an aircraft provided in an embodiment of the present application;

[0026] Figure 2 A schematic diagram of a flow chart of a method for measuring the altitude of an aircraft provided in an embodiment of the present application;

[0027] Figure 3 A schematic diagram of a flow chart of a method for measuring the altitude of an aircraft provided in an embodiment of the present application;

[0028] Figure 4 A schematic diagram of a flow chart of a method for measuring the altitude of an aircraft provided in an embodiment of the present application;

[0029] Figure 5 A schematic diagram of the structure of an altitude measuring device for an aircraft provided in an embodiment of the present application;

[0030] Figure 6 A schematic diagram of the structure of a height measurement device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0032] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0033] In the description of the present application, it should be noted that if the terms "upper", "lower", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or is the orientation or position relationship in which the product of the application is usually placed when used. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0034] In addition, the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0035] It should be noted that, in the absence of conflict, the features in the embodiments of the present application may be combined with each other.

[0036] Figure 1 A flowchart of a method for measuring the height of an aircraft provided in an embodiment of the present application; a processing module applied to a height measuring device loaded on an aircraft, the height measuring device further comprising: a radio frequency module, a front-end transmitting module and a front-end receiving module; Figure 1 As shown, the method includes:

[0037] Step 110: Control the front-end transmitting module to send out a frequency modulated continuous wave signal through the radio frequency module.

[0038] Among them, the core tasks of the RF module cover two aspects. First, it needs to modulate the command information to be sent to the RF tag onto the RF signal and send it out through the transmitting antenna. These RF signals propagate to the RF tag in space, triggering the tag to respond, thereby forming a reflected echo signal, and then returning to the receiving antenna. Secondly, the RF module also needs to perform necessary processing on the returned echo signal, demodulate and extract the data returned by the RF tag. Among them, the transmitting antenna is used to send electromagnetic wave signals, and the front-end transmitting module is an intermediate module located between the RF module and the transmitting antenna, and its function is to send electromagnetic wave signals; the transmitting antenna realizes the signal transmission function through the front-end transmitting module. The receiving antenna is used to receive electromagnetic wave signals, and the front-end receiving module is an intermediate module located between the RF module and the receiving antenna, and its function is to receive electromagnetic wave signals; the receiving antenna realizes the signal receiving function through the front-end receiving module.

[0039] The front-end transmitting module performs transmission amplification, filtering, power detection, control, switching, etc. of the RF signal.

[0040] Frequency modulated continuous wave radar mainly has several types of frequency-time functions such as triangular wave, sawtooth wave, and sine wave. At present, civil radar usually uses sawtooth wave. In practical applications, in order to ensure high precision, the bandwidth of the radar needs to be as wide as possible, and the frequency modulated continuous sawtooth wave radar transmits a frequency modulated signal, which is a sine wave signal whose frequency increases with time.

[0041] Exemplarily, the generation function of the frequency modulated continuous wave signal can be shown as the following formula (1):

[0042]

[0043] Among them, A t represents the amplitude of the FM continuous wave signal; f0 represents the carrier frequency of the FM continuous wave signal; t represents time; Indicates the initial phase of the FM continuous wave signal; μ indicates the FM slope; μ = B / T m , B represents the bandwidth of the frequency modulated continuous wave signal, that is, the frequency modulation bandwidth, T m Indicates the frequency modulation period.

[0044] Step 120: Acquire a first digital echo signal of a receiving channel and a second digital echo signal of a coupling channel acquired by the RF module from an echo signal received by the front-end receiving module.

[0045] Among them, the front-end receiving module performs reception, amplification, filtering, power detection, control, switching, etc. of the RF signal.

[0046] The receiving channel refers to the part used in the receiver to track, process and measure satellite signals. It is composed of radio components, digital circuits and other hardware and dedicated software. A channel can only track a signal of a certain frequency from a satellite at a time. The design and performance of the receiving channel directly affect the quality and efficiency of satellite communications.

[0047] A coupling channel is a channel that couples the signals between two signal channels with a certain coupling coefficient. The signals between different channels are transmitted to each other through the function of capacitors, achieving a certain degree of signal transmission. The application of coupling channels is not limited to audio circuits, but also extends to high-speed digital communications, image processing and other fields.

[0048] Exemplarily, the first digital echo signal of the collected receiving channel is shown in the following formula (2):

[0049]

[0050] Among them, A RX Represents the amplitude of the first digital echo signal of the receiving channel; t h =2h / c, where h is the estimated altitude of the aircraft and c is the speed of light; Indicates the initial phase of the first digital echo signal of the receiving channel.

[0051] Exemplarily, the collected second digital echo signal of the coupling channel is shown in the following formula (3):

[0052]

[0053] Among them, A RXFB Indicates the amplitude of the second digital echo signal of the coupling channel; Indicates the initial phase of the second digital echo signal of the coupling channel.

[0054] Step 130: Determine a start time for frequency mixing de-skew according to the estimated altitude of the aircraft, the preset constant beat frequency, and the preset constant frequency modulation parameters.

[0055] The estimated altitude is the altitude value obtained by the aircraft in the last measurement cycle.

[0056] Existing radar altimeters are mainly based on two working systems: a single constant beat frequency and a uniform multi-channel constant beat frequency. The altitude measurement device installed on the aircraft used in the altitude measurement method of an aircraft provided in an embodiment of the present application is a radar altitude measurement device (altimeter) based on a single constant beat frequency working system.

[0057] The constant beat frequency system is a signal processing technique that allows the measurement and analysis of various physical phenomena in experiments by keeping the frequency difference between two or more signals constant. When the frequency difference between two signals is kept constant, their combined signal will produce a stable amplitude, which is called the "beat frequency". By measuring the change in the beat frequency amplitude, information about parameters such as signal frequency and phase can be obtained.

[0058] The constant frequency modulation parameters may be a constant frequency modulation slope, a constant frequency modulation bandwidth, a constant frequency modulation period, etc.

[0059] Mixing de-skewing is a signal processing technique mainly used in radar systems, especially in the processing of linear frequency modulation signals. This technique uses a mixing operation, namely de-skewing, to achieve matched filtering, thereby improving the signal-to-noise ratio of the signal, enhancing the signal component while weakening the noise component, and ultimately achieving the purpose of enhancing the signal-to-noise ratio and range resolution of the radar signal. De-skewing is essentially a special matched filtering, in which the performance of the filter is consistent with the characteristics of the signal to maximize the ratio of the instantaneous power of the output signal to the average power of the noise, thereby optimizing the reception and processing of the signal.

[0060] This step may determine the start time for frequency mixing de-skew based on a first preset formula according to an estimated altitude of the aircraft, a preset constant beat frequency, and a preset constant frequency modulation parameter.

[0061] Step 140: Perform frequency mixing and de-skewing processing on the second digital echo signal according to the start time to obtain a beat signal.

[0062] This step can be based on the second preset formula and according to the start time, perform mixing and de-skewing processing on the second digital echo signal to obtain a beat signal.

[0063] The beat signal refers to the periodic change formed when two wave signals of different frequencies interact with each other. The amplitude increases and decreases periodically according to the difference between the two frequencies, resulting in wave amplitude modulation and ups and downs.

[0064] Step 150: Determine the altitude value of the aircraft in the current measurement cycle according to the beat signal and the start time.

[0065] This step can be based on the third preset formula, according to the beat signal and the start time, to determine the altitude value of the aircraft in the current measurement cycle.

[0066] The method for measuring the height of an aircraft provided in an embodiment of the present application, first, controls the front-end transmitting module to send a frequency modulated continuous wave signal through the radio frequency module; secondly, obtains the first digital echo signal of the receiving channel and the second digital echo signal of the coupling channel collected by the radio frequency module from the echo signal received by the front-end receiving module; thirdly, determines the starting time for mixing and de-skewing according to the estimated height of the aircraft, the preset constant beat frequency and the preset constant frequency modulation parameter; then, performs mixing and de-skewing processing on the second digital echo signal according to the starting time to obtain the beat signal; finally, determines the height value of the aircraft in the current measurement cycle according to the beat signal and the starting time. Under the condition of maintaining the preset constant beat frequency and the preset constant frequency modulation parameter, by determining the starting time for mixing and de-skewing, then generating a digital mixing signal based on the starting time to perform mixing and de-skewing processing on the second digital echo signal, and then determining the height value of the aircraft in the current measurement cycle based on the starting time, thus improving the measurement accuracy and precision of the aircraft height.

[0067] Compared with the traditional constant beat frequency system height measurement device, the height measurement device based on the height measurement method of the aircraft provided by the embodiment of the present application has the advantages of low requirements on the hardware system of the height measurement device, simple software implementation, and the ability to expand the height measurement range of the height measurement device. Since it can maintain a constant frequency modulation period while maintaining a constant beat frequency, the height measurement device based on the height measurement method of the aircraft provided by the embodiment of the present application has the advantages of strong compatibility, high stability, and strong anti-interference ability.

[0068] The following is an example to explain the process of determining the start time for frequency mixing de-skewing in the above embodiment. The preset constant frequency modulation parameters include: frequency modulation bandwidth and frequency modulation period; the above step 130 may further include the following steps:

[0069] The start time is calculated based on the estimated altitude of the aircraft, the preset constant beat frequency, the frequency modulation bandwidth and the frequency modulation period.

[0070] For example, the starting time t dechirp The calculation formula of the first preset formula can be shown as follows:

[0071]

[0072] Wherein, h represents the estimated altitude of the aircraft, which is the altitude value obtained by the aircraft in the last measurement cycle; Fb represents the preset constant beat frequency.

[0073] The method for measuring the altitude of an aircraft provided in an embodiment of the present application calculates the start time according to the estimated altitude of the aircraft, the preset constant beat frequency, the frequency modulation bandwidth and the frequency modulation period. The start time for mixing and de-skewing is calculated while maintaining the preset constant beat frequency, the frequency modulation bandwidth and the frequency modulation period, so that the calculation accuracy can be improved.

[0074] The process of obtaining the beat signal in the above embodiment is explained as follows in combination with examples. Figure 2 The following is a flow chart of a method for measuring the height of an aircraft provided in an embodiment of the present application. Figure 2 As shown, the above step 140 may further include the following steps 210 to 250:

[0075] Step 210: Determine a digital mixing signal of a receiving channel as a first digital mixing signal.

[0076] Exemplarily, the first digital mixing signal S M The formula for determining (t) is shown in the following formula (5):

[0077] S M (t) = cos(2πf0t),0 <t<T m (5)

[0078] Step 220: Use the first digital mixing signal to perform digital mixing processing on the first digital echo signal to obtain a first target digital mixing signal of the receiving channel.

[0079] Exemplarily, the digital mixing process in this step can be operated according to the following formula (6):

[0080] S RX (t) = S RX (t)⊙conj(S M (t))(6)

[0081] The first target digital mixing signal of the receiving channel obtained after the mixing process is shown in the following formula (7):

[0082]

[0083] Step 230: Generate a digital mixing signal of the coupling channel according to the start time as a second digital mixing signal.

[0084] Exemplarily, the second digital mixing signal S M (tt dechirp The formula for determining ) is shown in the following formula (8):

[0085] s M (tt dechirp )=cos(2πf0(ttdechirp )),0 <t<T m (8)

[0086] Among them, t dechirp Indicates the start time for mixer de-skew.

[0087] Step 240: Use the second digital mixing signal to perform digital mixing processing on the first digital echo signal to obtain a second target digital mixing signal of the coupling channel.

[0088] Exemplarily, the digital mixing process in this step can be operated according to the following formula (9):

[0089] S RXFB (t) = S RXFB (t)⊙conj(S c (tt dechirp )) (9)

[0090] The second target digital mixing signal of the coupling channel obtained after the mixing process is shown in the following formula (10):

[0091]

[0092] Step 250: Use the second target digital mixing signal to perform mixing and de-skewing processing on the first target digital mixing signal to obtain a beat signal.

[0093] Exemplarily, the mixing de-skewing process, that is, the second formula above, can be expressed as the following formula (11):

[0094] S c (t) = S RX t⊙conj(S RXFB (t)) (11)

[0095] The beat signal S obtained by mixing and de-skewing c (t) is shown in the following formula (12):

[0096]

[0097] Among them, A c Represents the amplitude of the beat signal, A c =A RX *A RXFB .

[0098] The method for measuring the altitude of an aircraft provided in an embodiment of the present application comprises the following steps: first, determining a digital mixing signal of a receiving channel as a first digital mixing signal; secondly, using the first digital mixing signal to perform digital mixing processing on a first digital echo signal to obtain a first target digital mixing signal of the receiving channel; thirdly, generating a digital mixing signal of a coupling channel as a second digital mixing signal according to a start time; then, using the second digital mixing signal to perform digital mixing processing on the first digital echo signal to obtain a second target digital mixing signal of the coupling channel; finally, using the second target digital mixing signal to perform mixing and de-skewing processing on the first target digital mixing signal to obtain a beat signal. The first target digital mixing signal is obtained by performing mixing and de-skewing processing on the first digital echo signal by generating a digital mixing signal, the second target digital mixing signal is obtained by performing mixing and de-skewing processing on the second digital mixing signal by generating a digital mixing signal by starting time, and the beat signal is obtained by performing mixing and de-skewing processing on the first digital echo signal by using the second target digital mixing signal, so that the obtained beat signal is more accurate.

[0099] The following is an explanation of the process of determining the altitude value of the aircraft in the current measurement period in the above embodiment with reference to examples. Figure 3 The following is a flow chart of a method for measuring the height of an aircraft provided in an embodiment of the present application. Figure 3 As shown, the above step 150 may further include the following steps 310 to 330:

[0100] Step 310: Perform frequency domain transformation on the beat signal to obtain a spectrum signal of the beat signal.

[0101] Among them, frequency domain transformation refers to transforming complex time signals or space signals into a structural form represented by frequency components.

[0102] Step 320: Perform spectrum frontier detection on the spectrum signal to obtain target spectrum parameters of the beat signal.

[0103] Among them, spectrum frontier detection helps solve the contradiction between the growing communication demand and limited spectrum resources by detecting idle spectrum resources. The key to spectrum frontier detection is to discover and utilize those underutilized spectrum resources, thereby improving the efficiency and reliability of the entire communication system. The implementation of this technology relies on cognitive radio technology, which can intelligently perceive and adapt to changes in the wireless environment and dynamically select the best communication frequency band to optimize communication quality and efficiency.

[0104] The implementation of spectrum frontier detection involves a variety of technologies and methods, including but not limited to energy detection methods, matched filter detection, etc. The energy detection method determines whether the spectrum is occupied by comparing the received signal energy with the preset threshold value. Matched filter detection is a more advanced method that requires maximizing the signal-to-noise ratio through a matched filter when the characteristics of the primary user signal are known, thereby improving the accuracy of detection.

[0105] Step 330: Calculate the altitude value of the aircraft in the current measurement period according to the target spectrum parameters and the start time.

[0106] This step can be based on the third preset formula and the target spectrum parameters and the start time obtained from the beat signal to calculate the altitude value of the aircraft in the current measurement period.

[0107] The method for measuring the height of an aircraft provided in the embodiment of the present application first performs frequency domain transformation on the beat signal to obtain the spectrum signal of the beat signal; secondly, performs spectrum frontier detection on the spectrum signal to obtain the target spectrum parameter of the beat signal; finally, the height value of the aircraft in the current measurement cycle is calculated according to the target spectrum parameter and the start time. The height value of the aircraft in the current measurement cycle is calculated by the start time, thus improving the accuracy of the determined height value.

[0108] The process of obtaining the spectrum signal of the beat signal in the above embodiment is explained by way of example in combination with the following examples. The above step 310 may further include the following steps:

[0109] The phase of the beat signal is differentiated to obtain the instantaneous frequency signal of the beat signal as a spectrum signal.

[0110] For example, frequency domain transformation, that is, differential processing f b (t) can be operated according to the following formula (13):

[0111] f b (t) = μ(t h -t dechirp )(13)

[0112] Among them, f b (t) represents the instantaneous frequency signal of the beat signal.

[0113] The method for measuring the altitude of an aircraft provided in the embodiment of the present application performs differential processing on the phase of the beat signal to obtain the instantaneous frequency signal of the beat signal as the spectrum signal, thereby realizing frequency domain transformation of the beat signal.

[0114] The following is an example of the process of calculating the altitude value of the aircraft in the current measurement period in the above embodiment. The above step 330 may further include the following steps:

[0115] The altitude value of the aircraft in the current measurement period is calculated based on the target spectrum parameters, the preset constant frequency modulation parameters and the start time.

[0116] The preset constant frequency modulation parameters include: frequency modulation bandwidth and frequency modulation period. The above steps may further include the following steps 410 and 420:

[0117] Step 410: Calculate the frequency modulation slope according to the frequency modulation bandwidth and the frequency modulation period.

[0118] Among them, the frequency modulation slope μ=B / T m , B represents the bandwidth of the frequency modulated continuous wave signal, that is, the frequency modulation bandwidth, T m Indicates the frequency modulation period.

[0119] Step 420: Calculate the altitude value of the aircraft in the current measurement period according to the target spectrum parameters, the frequency modulation slope, and the start time.

[0120] Exemplarily, the calculation formula of the height value, that is, the third preset formula mentioned above, can be shown as the following formula (14):

[0121]

[0122] Among them, f b Represents the target spectrum parameters.

[0123] The method for measuring the altitude of an aircraft provided in the embodiment of the present application first calculates the frequency modulation slope according to the frequency modulation bandwidth and the frequency modulation period; secondly, calculates the altitude value of the aircraft in the current measurement period according to the target spectrum parameter, the frequency modulation slope and the start time. In this way, the altitude value of the aircraft in the current measurement period is calculated by the start time, which improves the accuracy of the determined altitude value.

[0124] After introducing the altitude measurement method of an aircraft according to an exemplary embodiment of the present disclosure, next, referring to Figure 5 An altitude measuring device 500 for an aircraft according to an exemplary embodiment of the present disclosure will be described.

[0125] refer to Figure 5As shown, the height measurement device 500 of an aircraft includes: a transmitting module 510, which is configured to control the front-end transmitting module to send a frequency modulated continuous wave signal through the radio frequency module; a receiving module 520, which is configured to obtain a first digital echo signal of a receiving channel and a second digital echo signal of a coupling channel acquired by the radio frequency module from an echo signal received by the front-end receiving module; a determining module 530, which is configured to determine a starting time for frequency mixing and de-skewing according to an estimated height of the aircraft, a preset constant beat frequency and a preset constant frequency modulation parameter; the estimated height is the height value obtained by the aircraft in the last measurement cycle; according to the starting time and the second digital echo signal, the first digital echo signal is subjected to frequency mixing and de-skewing processing to obtain a beat signal; according to the beat signal and the starting time, the height value of the aircraft in the current measurement cycle is determined.

[0126] In one embodiment, the preset constant frequency modulation parameters include: frequency modulation bandwidth and frequency modulation period; the determination module 530 is configured to: calculate the start time according to the estimated altitude of the aircraft, the preset constant beat frequency, the frequency modulation bandwidth and the frequency modulation period.

[0127] In one embodiment, the determination module 530 is configured to: determine a digital mixing signal of a receiving channel as a first digital mixing signal; use the first digital mixing signal to perform digital mixing processing on the first digital echo signal to obtain a first target digital mixing signal of the receiving channel; generate a digital mixing signal of a coupling channel according to a start time as a second digital mixing signal; use the second digital mixing signal to perform digital mixing processing on the first digital echo signal to obtain a second target digital mixing signal of the coupling channel; use the second target digital mixing signal to perform mixing de-skew processing on the first target digital mixing signal to obtain a beat signal.

[0128] In one embodiment, the determination module 530 is configured to: perform frequency domain transformation on the beat signal to obtain a spectrum signal of the beat signal; perform spectrum front detection on the spectrum signal to obtain target spectrum parameters of the beat signal; and calculate the altitude value of the aircraft in the current measurement period based on the target spectrum parameters and the start time.

[0129] In one implementation, the determination module 530 is configured to: perform differentiation processing on the phase of the beat signal to obtain an instantaneous frequency signal of the beat signal as a spectrum signal.

[0130] In one implementation, the determination module 530 is configured to calculate the altitude value of the aircraft in the current measurement period according to the target spectrum parameters, the preset constant frequency modulation parameters, and the start time.

[0131] In one embodiment, the preset constant frequency modulation parameters include: frequency modulation bandwidth and frequency modulation period; the determination module 530 is configured to: calculate the frequency modulation slope according to the frequency modulation bandwidth and the frequency modulation period; calculate the altitude value of the aircraft in the current measurement period according to the target spectrum parameters, the frequency modulation slope and the start time.

[0132] The above-mentioned device is used to execute the method provided by the aforementioned embodiment, and its implementation principle and technical effect are similar, which will not be repeated here.

[0133] The above modules may be one or more integrated circuits configured to implement the above methods, such as one or more application specific integrated circuits (ASICs), or one or more microprocessors, or one or more field programmable gate arrays (FPGAs). For another example, when a module is implemented in the form of a processing element scheduling program code, the processing element may be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call program code. For another example, these modules may be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0134] Figure 6 This is a schematic diagram of a height measuring device 600 provided in an embodiment of the present application. The device may be integrated into a terminal device or a chip of a terminal device. The terminal may be a computing device with data processing capabilities.

[0135] The device includes: a processing module 601, a radio frequency module 602, a front-end transmitting module 603, a front-end receiving module 604, a storage medium 605 and a bus 606. The front-end transmitting module 603 and the front-end receiving module 604 are both connected to the radio frequency module 602, the radio frequency module 602 is connected to the processing module 601, and the processing module 601 is connected to the storage medium 605, wherein the storage medium may be DDR (Double Data Rate, double rate synchronous dynamic random access memory) and / or FLASH (Flash EEPROM Memory, flash memory), and the processing module 601 may also be connected to a recorder through a recorder interface, and connected to other devices through an external interface;

[0136] The storage medium 605 stores program instructions executable by the processing module 601. When the height measurement device 600 is running, the processing module 601 communicates with the storage medium 605 via the bus 606. The processing module 601 executes the program instructions to perform the above method embodiment. The specific implementation method and technical effect are similar and will not be repeated here.

[0137] Optionally, the present invention also provides a program product, such as a computer-readable storage medium, comprising a program, which is used to execute the above method embodiment when executed by a processor.

[0138] In the several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0139] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0140] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0141] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor (English: processor) to perform some steps of the methods of various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (English: Read-Only Memory, abbreviated: ROM), random access memory (English: Random Access Memory, abbreviated: RAM), disk or optical disk and other media that can store program codes.

[0142] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for measuring the altitude of an aircraft, characterized in that: A processing module applied to an altitude measuring device loaded on the aircraft, wherein the altitude measuring device further comprises: a radio frequency module, a front-end transmitting module and a front-end receiving module; the method comprises: Control the front-end transmitting module to emit a frequency modulated continuous wave signal through the radio frequency module; Acquire a first digital echo signal of a receiving channel and a second digital echo signal of a coupling channel acquired by the RF module from an echo signal received by the front-end receiving module; Determining a starting time for frequency mixing de-skewing according to an estimated altitude value of the aircraft, a preset constant beat frequency, and a preset constant frequency modulation parameter; the estimated altitude value is an altitude value obtained by the aircraft in the last measurement cycle; According to the start time and the second digital echo signal, performing mixing and de-skewing processing on the first digital echo signal to obtain a beat signal; The altitude value of the aircraft in the current measurement cycle is determined according to the beat signal and the start time.

2. The method according to claim 1, characterized in that The preset constant frequency modulation parameters include: frequency modulation bandwidth and frequency modulation period; the determining the starting time for frequency mixing de-skewing according to the estimated altitude of the aircraft, the preset constant beat frequency and the preset constant frequency modulation parameters includes: The start time is calculated according to the estimated altitude of the aircraft, the preset constant beat frequency, the frequency modulation bandwidth and the frequency modulation period.

3. The method according to claim 1, characterized in that The step of performing frequency mixing and de-skewing processing on the first digital echo signal according to the start time and the second digital echo signal to obtain a beat signal comprises: Determine a digital mixing signal of the receiving channel as a first digital mixing signal; Performing digital mixing processing on the first digital echo signal using the first digital mixing signal to obtain a first target digital mixing signal of the receiving channel; generating a digital mixing signal of the coupling channel as a second digital mixing signal according to the start time; Performing digital mixing processing on the first digital echo signal using the second digital mixing signal to obtain a second target digital mixing signal of the coupling channel; The second target digital mixing signal is used to perform mixing and de-skewing processing on the first target digital mixing signal to obtain the beat signal.

4. The method according to claim 1, characterized in that: Determining the altitude value of the aircraft in the current measurement cycle according to the beat signal and the start time includes: Performing frequency domain transformation on the beat signal to obtain a frequency spectrum signal of the beat signal; Performing spectrum frontier detection on the spectrum signal to obtain target spectrum parameters of the beat signal; The altitude value of the aircraft in the current measurement period is calculated according to the target frequency spectrum parameter and the start time.

5. The method according to claim 4, characterized in that The performing frequency domain transformation on the beat signal to obtain a spectrum signal of the beat signal includes: The phase of the beat signal is differentiated to obtain an instantaneous frequency signal of the beat signal as the spectrum signal.

6. The method according to claim 4, characterized in that The step of calculating the altitude value of the aircraft in the current measurement period according to the target spectrum parameter and the start time includes: The altitude value of the aircraft in the current measurement period is calculated according to the target frequency spectrum parameter, the preset constant frequency modulation parameter and the start time.

7. The method according to claim 6, characterized in that The preset constant frequency modulation parameters include: frequency modulation bandwidth and frequency modulation period; the calculating the altitude value of the aircraft in the current measurement period according to the target spectrum parameters, the preset constant frequency modulation parameters and the start time includes: Calculating a frequency modulation slope according to the frequency modulation bandwidth and the frequency modulation period; The altitude value of the aircraft in the current measurement period is calculated according to the target spectrum parameter, the frequency modulation slope and the start time.

8. An altitude measuring device for an aircraft, characterized in that: include: The transmitting module is configured to control the front-end transmitting module to send a frequency modulated continuous wave signal through the radio frequency module; A receiving module configured to obtain a first digital echo signal of a receiving channel and a second digital echo signal of a coupling channel acquired by the RF module from an echo signal received by the front-end receiving module; A determination module, configured to determine a start time for frequency mixing de-skewing according to an estimated altitude of the aircraft, a preset constant beat frequency, and a preset constant frequency modulation parameter; The estimated altitude is the altitude value obtained by the aircraft in the last measurement cycle; according to the start time and the second digital echo signal, the first digital echo signal is mixed and de-skewed to obtain a beat signal; according to the beat signal and the start time, the altitude value of the aircraft in the current measurement cycle is determined.

9. A height measuring device, characterized in that: The height measurement device comprises: a processing module, a radio frequency module, a front-end transmitting module, a front-end receiving module, a storage medium and a bus, wherein the processing module is connected to the radio frequency module, and the radio frequency module is respectively connected to the front-end transmitting module and the front-end receiving module; The storage medium stores program instructions executable by the processing module. When the height measuring device is running, the processing module communicates with the storage medium through the bus, and the processing module executes the program instructions to perform the steps of the height measurement method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the height measurement method according to any one of claims 1 to 7 are executed.

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