A multipath birth and death modeling method and device

Abstract

The present invention discloses a multipath generation and death modeling method and device, the method comprising: performing multipath quantity processing on M adjacent scenes to obtain M adjacent scenes with the same multipath quantity, M being a positive integer; performing phase processing on the M adjacent scenes with the same multipath quantity to obtain M adjacent scenes with continuous phases; and processing the M adjacent scenes with continuous phases to realize multipath generation and death between scenes with different speeds. The method of the present invention can not only simulate the change of the multipath quantity caused by scene change based on the simulator, but also realize the relative speed change between the transmitting and receiving ends, enriching the simulation scenes of the wireless channel simulator.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless communication channel simulation, and in particular to a multipath birth and death modeling method and device. Background Art

[0002] In wireless communication, signals travel from the transmitter to the receiver through different paths. The transmission characteristics of each path (such as reflection, diffraction, scattering, etc.) may cause signal attenuation and phase change. When these signals are superimposed at the receiver, a multipath effect will occur, which will affect the communication quality and may even cause inter-symbol interference (ISI). Multipath generation and death refers to the dynamic propagation environment in which multipath signals suddenly appear or disappear in an outdoor wireless channel. The process of signal strength change under multipath propagation conditions, that is, the phenomenon of enhancement (generation) and weakening (death) experienced by the signal when it propagates on different paths. In wireless communication, multipath generation and death refers to the signal reaching the receiver through different reflection, refraction and scattering paths. The signal strength and phase of each path are different and will change with time and environmental conditions, resulting in the amplitude and phase of the received signal showing random rapid fluctuations, which is the so-called fast fading.

[0003] There are two forms of multipath generation and death: one is amplitude change. When signals from different paths are superimposed at the receiving point, the signals sometimes enhance each other (Constructive Interference) and sometimes cancel each other (Destructive Interference), causing the signal strength to fluctuate, which directly affects the quality and stability of the communication link. The second is frequency selective fading. Due to the different lengths of each path, the difference in signal delay will lead to frequency selective fading, causing different frequency components to be attenuated to different degrees, which is particularly harmful to broadband communication systems and may increase the bit error rate of data packets. The process of simulating multipath generation and death by a wireless channel emulator can be used to test the receiver's resistance to the sudden disappearance or sudden appearance of multipath signals. The traditional simulation method of multipath generation and death in a wireless channel emulator generally uses multiple pure direct-line paths, which are realized by randomly adjusting the delays of these paths by the emulator. In the actual communication scene switching process, not only the number of multipaths changes, but also the running speed changes. The traditional multipath generation and death simulation method based on pure direct-line paths cannot fully reflect the above changes. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a multipath birth and death modeling method and device, based on a wireless channel simulator, focusing on solving the problems of inconsistent multipath numbers, discontinuous phases and inconsistent speeds in adjacent scenes. The present invention can not only simulate the change in the number of multipaths caused by scene changes based on the simulator, but also realize the relative speed change between the transmitting and receiving ends, enriching the simulation scenes of the wireless channel simulator.

[0005] In order to solve the above technical problem, a first aspect of an embodiment of the present invention discloses a multipath birth and death modeling method, the method comprising:

[0006] S1, perform multipath number processing on M adjacent scenes to obtain M adjacent scenes with the same multipath number, where M is a positive integer;

[0007] S2, performing phase processing on the M adjacent scenes having the same number of multipaths to obtain M adjacent scenes having continuous phases;

[0008] S3, processing the M adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds.

[0009] As an optional implementation manner, in the first aspect of the embodiment of the present invention, the performing multipath quantity processing on the M adjacent scenes to obtain M adjacent scenes with the same multipath quantity includes:

[0010] S11, obtaining the number of multipaths of M adjacent scenes;

[0011] S12, processing the multipath numbers of the M adjacent scenes to find the maximum multipath number N max,path ;

[0012] S13, according to the maximum number of multipaths N max,path , multipath quantity processing is performed on the M adjacent scenes to obtain M adjacent scenes with the same multipath quantity.

[0013] As an optional implementation manner, in the first aspect of the embodiment of the present invention, the performing phase processing on the M adjacent scenes having the same number of multipaths to obtain M adjacent scenes with continuous phases includes:

[0014] S21, performing impulse response calculation on the M adjacent scenes having the same number of multipaths to obtain M adjacent scene impulse responses;

[0015] S22, processing the M adjacent scene impulse responses to obtain M adjacent scenes with continuous phases.

[0016] As an optional implementation manner, in the first aspect of the embodiment of the present invention, the processing of the M adjacent scene impulse responses to obtain M adjacent scenes with continuous phases includes:

[0017] S221, processing the impulse responses of any two adjacent scenes to obtain the phase sequence θ corresponding to the last sample point of the impulse response of the previous scene in the two adjacent scenes and all multipaths 1 ,θ 2,…,θ N1 ], N1 is the number of multipaths in the previous scene between any two adjacent scenes;

[0018] S222, the phase sequence θ=[θ 1 ,θ 2 ,…,θ N1 ] as the initial phase of the latter scene in any two adjacent scenes, and M adjacent scenes with continuous phases are obtained.

[0019] As an optional implementation manner, in the first aspect of the embodiment of the present invention, the processing of the M phase-continuous adjacent scenes to achieve multipath generation and death between scenes of different speeds includes:

[0020] S31, processing any two phase-continuous adjacent scenes to obtain the half-wavelength sampling density ρ of the previous scene in the any two phase-continuous adjacent scenes 1 and the half-wavelength sampling density ρ of the latter scene 2 ;

[0021] S32, according to the half-wavelength sampling density ρ of the previous scene 1 and the half-wavelength sampling density ρ of the latter scenario 2 , multipath splicing is performed on any two adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds.

[0022] As an optional implementation, in the first aspect of the embodiment of the present invention, the processing of any two phase-continuous adjacent scenes obtains the half-wavelength sampling density ρ of the previous scene in the any two phase-continuous adjacent scenes. 1 and the half-wavelength sampling density ρ of the latter scene 2 ,include:

[0023] S311, processing any two phase-continuous adjacent scenes to obtain the velocity v of the previous scene of the any two phase-continuous adjacent scenes 1 and the speed v of the next scene 2 ;

[0024] S312, for the velocity v of the previous scene in any two adjacent scenes with continuous phases, 1 and the speed v of the latter scene 2 Processing is performed to obtain the half-wavelength sampling density ρ of the previous scene in any two adjacent scenes with continuous phases 1 and the half-wavelength sampling density ρ of the latter scene 2 .

[0025] As an optional implementation, in the first aspect of the embodiment of the present invention, the processing of any two phase-continuous adjacent scenes obtains the velocity v of the previous scene in the any two phase-continuous adjacent scenes. 1 and the speed v of the next scene 2 ,include:

[0026] S3111, using a preset first speed model, processing the interval between two sampling points in the previous scene in the adjacent scene and the sampling time between the two sampling points to obtain the speed v of the previous scene in the adjacent scene 1 ;

[0027] The preset first speed model is:

[0028]

[0029] Where, d 1 is the interval between two sampling points in the previous scene in the adjacent scene, t 01 is the sampling time between two sampling points in the previous scene in the adjacent scene;

[0030] S3112, using a preset second speed model, processing the interval between two sampling points in the next scene in the adjacent scene and the sampling time between the two sampling points to obtain the speed v of the next scene in the adjacent scene 2 ;

[0031] The preset second speed model is:

[0032]

[0033] Where, d 2 is the interval between two sampling points in the next scene in the adjacent scene, t 02 is the sampling time between two sampling points in the next scene in the adjacent scene.

[0034] As an optional implementation, in the first aspect of the embodiment of the present invention, the velocity v of the previous scene in any two adjacent scenes with continuous phases is 1 and the speed v of the latter scene 2 Processing is performed to obtain the half-wavelength sampling density ρ of the previous scene in any two adjacent scenes with continuous phases 1 and the half-wavelength sampling density ρ of the latter scene 2 ,include:

[0035] S3121, using the first half-wavelength sampling density calculation model, calculate the velocity v of the previous scene in the adjacent scene 1 Processing is performed to obtain the half-wavelength sampling density ρ of the previous scene in the adjacent scene1 ;

[0036] The first half-wavelength sampling density calculation model is:

[0037]

[0038] In the formula, F s is the baseband sampling rate, c is the speed of light, f center is the center frequency;

[0039] S3122, using the second half-wavelength sampling density calculation model, the velocity v of the next scene in the adjacent scene 2 Processing is performed to obtain the half-wavelength sampling density ρ of the next scene in the adjacent scene 2 ;

[0040] The second half-wavelength sampling density calculation model is:

[0041]

[0042] In the formula, F s is the baseband sampling rate, c is the speed of light, f center is the center frequency.

[0043] A second aspect of an embodiment of the present invention discloses a multipath birth and death modeling device, the device comprising:

[0044] A multipath quantity processing module is used to perform multipath quantity processing on M adjacent scenes to obtain M adjacent scenes with the same multipath quantity, where M is a positive integer;

[0045] A phase processing module, used to perform phase processing on the M adjacent scenes with the same number of multipaths to obtain M adjacent scenes with continuous phases;

[0046] The multipath generation and death module is used to process the M adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds.

[0047] As an optional implementation manner, in the second aspect of the embodiment of the present invention, the performing multipath quantity processing on the M adjacent scenes to obtain M adjacent scenes with the same multipath quantity includes:

[0048] S11, obtaining the number of multipaths of M adjacent scenes;

[0049] S12, processing the multipath numbers of the M adjacent scenes to find the maximum multipath number N max,path ;

[0050] S13, according to the maximum number of multipaths N max,path, multipath quantity processing is performed on the M adjacent scenes to obtain M adjacent scenes with the same multipath quantity.

[0051] As an optional implementation manner, in the second aspect of the embodiment of the present invention, the phase processing is performed on the M adjacent scenes having the same number of multipaths to obtain M adjacent scenes with continuous phases, including:

[0052] S21, performing impulse response calculation on the M adjacent scenes having the same number of multipaths to obtain M adjacent scene impulse responses;

[0053] S22, processing the M adjacent scene impulse responses to obtain M adjacent scenes with continuous phases.

[0054] As an optional implementation manner, in the second aspect of the embodiment of the present invention, the processing of the M adjacent scene impulse responses to obtain M adjacent scenes with continuous phases includes:

[0055] S221, processing the impulse responses of any two adjacent scenes to obtain the phase sequence θ corresponding to the last sample point of the impulse response of the previous scene in the two adjacent scenes and all multipaths 1 ,θ 2 ,…,θ N1 ], N1 is the number of multipaths in the previous scene between any two adjacent scenes;

[0056] S222, the phase sequence θ=[θ 1 ,θ 2 ,…,θ N1 ] as the initial phase of the latter scene in any two adjacent scenes, and M adjacent scenes with continuous phases are obtained.

[0057] As an optional implementation manner, in the second aspect of the embodiment of the present invention, the processing of the M phase-continuous adjacent scenes to achieve multipath generation and death between scenes of different speeds includes:

[0058] S31, processing any two phase-continuous adjacent scenes to obtain the half-wavelength sampling density ρ of the previous scene in the any two phase-continuous adjacent scenes 1 and the half-wavelength sampling density ρ of the latter scene 2 ;

[0059] S32, according to the half-wavelength sampling density ρ of the previous scene 1 and the half-wavelength sampling density ρ of the latter scenario 2 , multipath splicing is performed on any two adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds.

[0060] As an optional implementation, in the second aspect of the embodiment of the present invention, the processing of any two phase-continuous adjacent scenes obtains the half-wavelength sampling density ρ of the previous scene in the any two phase-continuous adjacent scenes. 1 and the half-wavelength sampling density ρ of the latter scene 2 ,include:

[0061] S311, processing any two phase-continuous adjacent scenes to obtain the velocity v of the previous scene of the any two phase-continuous adjacent scenes 1 and the speed v of the next scene 2 ;

[0062] S312, for the velocity v of the previous scene in any two adjacent scenes with continuous phases, 1 and the speed v of the latter scene 2 Processing is performed to obtain the half-wavelength sampling density ρ of the previous scene in any two adjacent scenes with continuous phases 1 and the half-wavelength sampling density ρ of the latter scene 2 .

[0063] As an optional implementation, in the second aspect of the embodiment of the present invention, the processing of any two phase-continuous adjacent scenes obtains the speed v1 of the previous scene and the speed v2 of the next scene in the any two phase-continuous adjacent scenes. 2 ,include:

[0064] S3111, using a preset first speed model, processing the interval between two sampling points in the previous scene in the adjacent scene and the sampling time between the two sampling points to obtain the speed v of the previous scene in the adjacent scene 1 ;

[0065] The preset first speed model is:

[0066]

[0067] Where, d 1 is the interval between two sampling points in the previous scene in the adjacent scene, t 01 is the sampling time between two sampling points in the previous scene in the adjacent scene;

[0068] S3112, using a preset second speed model, processing the interval between two sampling points in the next scene in the adjacent scene and the sampling time between the two sampling points to obtain the speed v of the next scene in the adjacent scene 2 ;

[0069] The preset second speed model is:

[0070]

[0071] Where, d 2 is the interval between two sampling points in the next scene in the adjacent scene, t 02 is the sampling time between two sampling points in the next scene in the adjacent scene.

[0072] As an optional implementation, in the second aspect of the embodiment of the present invention, the velocity v of the previous scene in any two adjacent scenes with continuous phases is 1 and the speed v of the latter scene 2 The half-wavelength sampling density ρ1 of the previous scene and the half-wavelength sampling density ρ of the next scene in any two phase-continuous adjacent scenes are obtained. 2 ,include:

[0073] S3121, using the first half-wavelength sampling density calculation model, calculate the velocity v of the previous scene in the adjacent scene 1 Processing is performed to obtain the half-wavelength sampling density ρ of the previous scene in the adjacent scene 1 ;

[0074] The first half-wavelength sampling density calculation model is:

[0075]

[0076] In the formula, F s is the baseband sampling rate, c is the speed of light, f center is the center frequency;

[0077] S3122, using the second half-wavelength sampling density calculation model, the velocity v of the next scene in the adjacent scene 2 Processing is performed to obtain the half-wavelength sampling density ρ of the next scene in the adjacent scene 2 ;

[0078] The second half-wavelength sampling density calculation model is:

[0079]

[0080] In the formula, F s is the baseband sampling rate, c is the speed of light, f center is the center frequency.

[0081] The third aspect of the present invention discloses another multipath birth and death modeling device, the device comprising:

[0082] A memory storing executable program code;

[0083] a processor coupled to the memory;

[0084] The processor calls the executable program code stored in the memory to execute part or all of the steps in the multipath birth and death modeling method disclosed in the first aspect of the embodiment of the present invention.

[0085] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0086] The present invention discloses a multipath generation and death modeling method and device, which processes the number of multipaths on M adjacent scenes to obtain M adjacent scenes with the same number of multipaths, where M is a positive integer; processes the phases of M adjacent scenes with the same number of multipaths to obtain M adjacent scenes with continuous phases; and processes M adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds. The method of the present invention can not only simulate the change in the number of multipaths due to scene changes based on a simulator, but also achieve the relative speed change between the transmitting and receiving ends, thus enriching the simulation scenes of the wireless channel simulator. As the speed increases, the channel jitter experienced becomes more intense, and at the same time, it meets the multipath generation and death design of achieving different speed scenes with the same baseband sampling rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0088] Figure 1 It is a flow chart of a multipath birth and death modeling method disclosed in an embodiment of the present invention;

[0089] Figure 2 It is a schematic diagram of multipath zero padding in different scenarios disclosed in an embodiment of the present invention;

[0090] Figure 3 is a schematic diagram of the phase discontinuity problem of splicing two adjacent scenes (LOS-LOS) disclosed in an embodiment of the present invention;

[0091] Figure 4 It is a display of the amplitude-frequency response problem of phase discontinuity noise of multipath birth and death in adjacent scenes disclosed in the embodiment of the present invention;

[0092] Figure 5 is a schematic diagram of the amplitude response of splicing adjacent scenes at different speeds disclosed in an embodiment of the present invention;

[0093] Figure 6 It is a structural schematic diagram of a multipath birth and death modeling device disclosed in an embodiment of the present invention;

[0094] Figure 7It is a structural schematic diagram of another multipath birth and death modeling device disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0095] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme 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. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0096] The terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, device, product or equipment that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or equipment.

[0097] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0098] The present invention discloses a multipath generation and death modeling method and device, the method comprising: performing multipath quantity processing on M adjacent scenes to obtain M adjacent scenes with the same multipath quantity, M being a positive integer; performing phase processing on the M adjacent scenes with the same multipath quantity to obtain M adjacent scenes with continuous phases; processing the M adjacent scenes with continuous phases to realize multipath generation and death between scenes with different speeds. The method of the present invention can not only simulate the change of the multipath quantity caused by scene change based on the simulator, but also realize the relative speed change between the transmitting and receiving ends, enriching the simulation scenes of the wireless channel simulator. The following are detailed descriptions respectively.

[0099] Embodiment 1

[0100] See also Figure 1 , Figure 1 is a flow chart of a multipath birth and death modeling method disclosed in an embodiment of the present invention. Figure 1The multipath birth and death modeling method described is applied to the field of wireless communication channel simulation technology to simulate the dynamic changes of channels during the communication scene switching process, which is not limited in the embodiments of the present invention. Figure 1 As shown, the multipath birth and death modeling method may include the following operations:

[0101] S1, perform multipath number processing on M adjacent scenes to obtain M adjacent scenes with the same multipath number, where M is a positive integer;

[0102] S2, performing phase processing on the M adjacent scenes having the same number of multipaths to obtain M adjacent scenes having continuous phases;

[0103] S3, processing the M adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds.

[0104] Optionally, performing multipath quantity processing on the M adjacent scenes to obtain M adjacent scenes having the same multipath quantity includes:

[0105] S11, obtaining the number of multipaths of M adjacent scenes;

[0106] S12, processing the multipath numbers of the M adjacent scenes to find the maximum multipath number N max,path ;

[0107] S13, according to the maximum number of multipaths N max,path , multipath quantity processing is performed on the M adjacent scenes to obtain M adjacent scenes with the same multipath quantity.

[0108] Optionally, performing phase processing on the M adjacent scenes having the same number of multipaths to obtain M adjacent scenes having continuous phases includes:

[0109] S21, performing impulse response calculation on the M adjacent scenes having the same number of multipaths to obtain M adjacent scene impulse responses;

[0110] S22, processing the M adjacent scene impulse responses to obtain M adjacent scenes with continuous phases.

[0111] Optionally, the processing the M adjacent scene impulse responses to obtain M adjacent scenes with continuous phases includes:

[0112] S221, processing the impulse responses of any two adjacent scenes to obtain the phase sequence θ corresponding to the last sample point of the impulse response of the previous scene in the two adjacent scenes and all multipaths 1 ,θ 2 ,…,θ N1], N1 is the number of multipaths in the previous scene between any two adjacent scenes;

[0113] S222, the phase sequence θ=[θ 1 ,θ 2 ,…,θ N1 ] as the initial phase of the latter scene in any two adjacent scenes, and M adjacent scenes with continuous phases are obtained.

[0114] Optionally, the processing of the M phase-continuous adjacent scenes to achieve multipath generation and death between scenes with different speeds includes:

[0115] S31, processing any two phase-continuous adjacent scenes to obtain the half-wavelength sampling density ρ of the previous scene in the any two phase-continuous adjacent scenes 1 and the half-wavelength sampling density ρ of the latter scene 2 ;

[0116] S32, according to the half-wavelength sampling density ρ of the previous scene 1 and the half-wavelength sampling density ρ of the latter scenario 2 , multipath splicing is performed on any two adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds.

[0117] Optionally, the processing of any two phase-continuous adjacent scenes obtains the half-wavelength sampling density ρ of the previous scene in the any two phase-continuous adjacent scenes. 1 and the half-wavelength sampling density ρ of the latter scene 2 ,include:

[0118] S311, processing any two phase-continuous adjacent scenes to obtain the velocity v of the previous scene of the any two phase-continuous adjacent scenes 1 and the speed v of the next scene 2 ;

[0119] S312, for the velocity v of the previous scene in any two adjacent scenes with continuous phases, 1 and the speed v of the latter scene 2 Processing is performed to obtain the half-wavelength sampling density ρ of the previous scene in any two adjacent scenes with continuous phases 1 and the half-wavelength sampling density ρ of the latter scene 2 .

[0120] Optionally, the processing of any two adjacent scenes with continuous phases obtains the velocity v of the previous scene in the any two adjacent scenes with continuous phases. 1 and the speed v of the next scene 2 ,include:

[0121] S3111, using a preset first speed model, processing the interval between two sampling points in the previous scene in the adjacent scene and the sampling time between the two sampling points to obtain the speed v of the previous scene in the adjacent scene 1 ;

[0122] The preset first speed model is:

[0123]

[0124] Where, d 1 is the interval between two sampling points in the previous scene in the adjacent scene, t 01 is the sampling time between two sampling points in the previous scene in the adjacent scene;

[0125] S3112, using a preset second speed model, processing the interval between two sampling points in the next scene in the adjacent scene and the sampling time between the two sampling points to obtain the speed v of the next scene in the adjacent scene 2 ;

[0126] The preset second speed model is:

[0127]

[0128] Where, d 2 is the interval between two sampling points in the next scene in the adjacent scene, t 02 is the sampling time between two sampling points in the next scene in the adjacent scene.

[0129] Optionally, the velocity v of the previous scene in any two adjacent scenes with continuous phases is 1 and the speed v of the latter scene 2 Processing is performed to obtain the half-wavelength sampling density ρ of the previous scene in any two adjacent scenes with continuous phases 1 and the half-wavelength sampling density ρ of the latter scene 2 ,include:

[0130] S3121, using the first half-wavelength sampling density calculation model, calculate the velocity v of the previous scene in the adjacent scene 1 Processing is performed to obtain the half-wavelength sampling density ρ of the previous scene in the adjacent scene 1 ;

[0131] The first half-wavelength sampling density calculation model is:

[0132]

[0133] In the formula, F sis the baseband sampling rate, c is the speed of light, f center is the center frequency;

[0134] S3122, using the second half-wavelength sampling density calculation model, the velocity v of the next scene in the adjacent scene 2 Processing is performed to obtain the half-wavelength sampling density ρ of the next scene in the adjacent scene 2 ;

[0135] The second half-wavelength sampling density calculation model is:

[0136]

[0137] In the formula, F s is the baseband sampling rate, c is the speed of light, f center is the center frequency.

[0138] It can be seen that the present invention discloses a multipath generation and death modeling method and device, which processes the number of multipaths for M adjacent scenes to obtain M adjacent scenes with the same number of multipaths, where M is a positive integer; performs phase processing on M adjacent scenes with the same number of multipaths to obtain M adjacent scenes with continuous phases; and processes M adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds. The method of the present invention can not only simulate the change in the number of multipaths due to scene changes based on the simulator, but also achieve the relative speed change between the transmitting and receiving ends, enriching the simulation scenes of the wireless channel simulator. As the speed increases, the channel jitter experienced becomes more severe, and at the same time, it meets the design of realizing multipath generation and death for scenes with different speeds with the same baseband sampling rate.

[0139] Embodiment 2

[0140] The traditional simulation method of multipath generation and death in a wireless channel emulator generally uses multiple pure direct-view paths, and the emulator randomly adjusts the delay of these paths to achieve this. In the actual communication scene switching process, not only the number of multipaths changes, but also the running speed changes. The traditional multipath generation and death simulation method based on pure direct-view paths cannot fully reflect the above changes. This embodiment implements a multipath generation and death modeling method based on a wireless channel emulator, which can not only simulate the change in the number of multipaths caused by scene changes based on the emulator, but also realize the relative speed change between the transmitting and receiving ends, enriching the simulation scene of the wireless channel emulator.

[0141] From the perspective of signal processing, the switching between the two scenes will cause changes in the number of multipaths and phase discontinuity caused by the splicing of channel modeling scenes. The present invention focuses on solving the problems of inconsistent multipath numbers, phase discontinuity and speed inconsistency in adjacent scenes.

[0142] (1) First, deal with the inconsistency of the number of multipaths in adjacent scenes, and follow the steps below:

[0143] ① Determine the number of multipaths N in the scene with the largest number of multipaths among all scenes max,path

[0144] ② For other scenarios, use N max,path Based on this, the number of multipaths in all scenarios is made consistent by padding with zeros.

[0145] ③ Such as Figure 2 As shown, there are 3 scenes in total, among which N max,path =3, the third path of scene 1 and the second and third paths of scene 3 are padded with zeros respectively. After the padded with zeros, the three scenes form a unified scene with a total of three paths.

[0146] (2) Solving the phase discontinuity problem

[0147] When there is a phase difference between the multipaths of adjacent scenes, direct splicing will cause phase discontinuity, which may seriously affect the demodulation of the receiver, such as Figure 3 shown.

[0148] After splicing the above adjacent scenes, the amplitude-frequency response of the spliced ​​scene is plotted as follows: Figure 4 As shown in the figure, although the amplitudes of the two are consistent after splicing, the noise frequency domain impulse response will be affected due to the phase discontinuity at the splicing point.

[0149] This scenario is handled as follows:

[0150] ① Determine the phase sequence of all multipaths corresponding to the last sample point of the previous scene channel impulse response in the adjacent scene θ=[θ 1 ,θ 2 ,…,θ N1 ], N1 is the number of multipaths in the previous scene;

[0151] ② Take θ as the initial phase in the next scene;

[0152] ③ If there is an inconsistency in the number of multipaths in adjacent scenes, the multipath zero filling solution in step (1) can be used.

[0153] (3) Speed ​​inconsistency problem in adjacent scenes

[0154] In the case of inconsistent speeds, channel modeling is generally performed separately, but different speeds will result in different baseband sampling rates, and the model cannot be directly and rigidly spliced ​​to simulate multipath birth and death. In order to achieve splicing of two different scenarios with the same baseband sampling rate, it can be assumed that the half-wavelength sampling density is ρ, which represents the number of sampling points on half the wavelength length during the modeling process, and the interval between two sampling points is d = λ / 2ρ, where λ represents the wavelength.

[0155]

[0156] Among them, f center is the center frequency, v represents the terminal running speed, Ω is the incoming wave angle, v=d / t 0 , t 0 represents the sampling time between two sample points. Substituting v into formula (1) yields

[0157]

[0158] The baseband sampling rate is F s =1 / t 0 , then formula (2) can be expressed as:

[0159]

[0160] where f d,max =v / cf center represents the maximum Doppler frequency shift. When the terminal velocity v is constant, f d,max For multipath birth and death scenarios with different moving speeds, limited by the implementation method and overall resources of the wireless channel emulator, F in formula (3) s Generally, it keeps a constant value. For the two scenarios, the channel impulse response is

[0161]

[0162] where ρ 1 represents the half-wavelength sampling density of the scene before multipath generation and death, ρ 2 It represents the half-wavelength sampling density of the scene after multipath generation and death. Formula (4) shows that by adjusting the half-wavelength sampling density, the multipath generation and death between two different speed scenes can be realized through channel modeling.

[0163] Through channel modeling, two adjacent scenarios are set up: the density of the first scenario is set to 16 for half wavelength and the moving speed is 3 km / h, and the density of the second scenario is set to 8 for half wavelength and the moving speed is 6 km / h. According to formula (4), the baseband sampling rates of the two scenarios are consistent. After splicing the multipath, the amplitude response is plotted, as shown in Figure 5 As shown. Figure 5 It can be seen that as the speed increases, the channel jitter experienced becomes more severe, while conforming to the multipath birth and death design that realizes different speed scenarios with the same baseband sampling rate.

[0164] Embodiment 3

[0165] See also Figure 6 , Figure 6 Schematic diagram of a multipath birth and death modeling device disclosed in an embodiment of the present invention. Figure 6The described multipath birth and death modeling device is applied to the technical field of wireless communication channel simulation to simulate the dynamic change of the channel during the communication scene switching process, which is not limited in the embodiment of the present invention.

[0166] like Figure 6 As shown, the multipath birth and death modeling device may include the following operations:

[0167] S301, a multipath quantity processing module, configured to perform multipath quantity processing on M adjacent scenes to obtain M adjacent scenes having the same multipath quantity, where M is a positive integer;

[0168] S302, a phase processing module, configured to perform phase processing on the M adjacent scenes having the same number of multipaths to obtain M adjacent scenes having continuous phases;

[0169] S303, a multipath generation and death module is used to process the M adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds.

[0170] Embodiment 4

[0171] See also Figure 7 , Figure 7 is a schematic diagram of the structure of another multipath birth and death modeling device disclosed in an embodiment of the present invention. Figure 7 The multipath generation and death modeling device described is applied to the field of wireless communication channel simulation technology to simulate the dynamic changes of channels during the communication scene switching process, which is not limited in the embodiments of the present invention. Figure 7 As shown, the multipath birth and death modeling device may include the following operations:

[0172] A memory 401 storing executable program codes;

[0173] a processor 402 coupled to the memory 401;

[0174] The processor 402 calls the executable program code stored in the memory 401 to execute the steps in the multipath birth and death modeling method described in the first embodiment and the second embodiment.

[0175] The device embodiments described above are only illustrative, wherein the modules described as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules, i.e., they may be located in one place, or they may be distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative work.

[0176] Through the specific description of the above embodiments, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the above technical solution can be essentially or partly contributed to the prior art in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, and the storage medium includes a read-only memory (ROM), a random access memory (RAM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), a one-time programmable read-only memory (OTPROM), an electronically erasable rewritable read-only memory (EEPROM), a compact disc (CD-ROM) or other optical disc storage, magnetic disk storage, magnetic tape storage, or any other computer-readable medium that can be used to carry or store data.

[0177] Finally, it should be noted that the multipath birth and death modeling method and device disclosed in the embodiment of the present invention discloses only the preferred embodiment of the present invention, which is only used to illustrate the technical solution of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multipath birth and death modeling method, characterized in that: The method comprises: S1, multipath quantity processing is performed on M adjacent scenes to obtain M adjacent scenes with the same multipath quantity, where M is a positive integer, including: S11, obtaining the number of multipaths of M adjacent scenes; S12, processing the multipath numbers of the M adjacent scenes to find the maximum multipath number N max,path ; S13, according to the maximum multipath number N max,path , performing multipath quantity processing on the M adjacent scenes to obtain M adjacent scenes having the same multipath quantity; S2, performing phase processing on the M adjacent scenes having the same number of multipaths to obtain M adjacent scenes having continuous phases, including: S21, performing impulse response calculation on the M adjacent scenes having the same number of multipaths to obtain M adjacent scene impulse responses; S22, processing the M adjacent scene impulse responses to obtain M adjacent scenes with continuous phases; S3, processing the M phase-continuous adjacent scenes to achieve multipath generation and death between scenes with different speeds, including: S31, processing any two phase-continuous adjacent scenes to obtain a half-wavelength sampling density ρ1 of a preceding scene and a half-wavelength sampling density ρ2 of a succeeding scene in the any two phase-continuous adjacent scenes; S32, performing multipath splicing on the arbitrary two phase-continuous adjacent scenes according to the half-wavelength sampling density ρ1 of the previous scene and the half-wavelength sampling density ρ2 of the subsequent scene, so as to realize multipath generation and death between scenes with different speeds.

2. The multipath birth and death modeling method according to claim 1, characterized in that: The processing of the M adjacent scene impulse responses to obtain M adjacent scenes with continuous phases includes: S221, processing the impulse responses of any two adjacent scenes to obtain the phase sequence θ corresponding to the last sample point of the impulse response of the previous scene in the any two adjacent scenes and all multipaths N1 ], N1 is the number of multipaths in the previous scene between any two adjacent scenes; S222, the phase sequence θ=[θ1, θ2, …, θ N1 ] as the initial phase of the latter scene in any two adjacent scenes, and M adjacent scenes with continuous phases are obtained.

3. The multipath birth and death modeling method according to claim 1, characterized in that: The processing of any two phase-continuous adjacent scenes to obtain the half-wavelength sampling density ρ1 of the previous scene and the half-wavelength sampling density ρ2 of the subsequent scene in the any two phase-continuous adjacent scenes includes: S311, processing any two phase-continuous adjacent scenes to obtain a speed v1 of a preceding scene and a speed v2 of a succeeding scene in the any two phase-continuous adjacent scenes; S312, processing the speed v1 of the previous scene and the speed v2 of the subsequent scene in the any two phase-continuous adjacent scenes to obtain the half-wavelength sampling density ρ1 of the previous scene and the half-wavelength sampling density ρ2 of the subsequent scene in the any two phase-continuous adjacent scenes.

4. The multipath birth and death modeling method according to claim 3, characterized in that: The processing of any two phase-continuous adjacent scenes to obtain the speed v1 of the previous scene and the speed v2 of the next scene in the any two phase-continuous adjacent scenes includes: S3111, using a preset first speed model, processing the interval between two sampling points in a previous scene in the adjacent scene and the sampling time between the two sampling points to obtain a speed v1 of the previous scene in the adjacent scene; The preset first speed model is: Where d1 is the interval between two sampling points in the previous scene in the adjacent scene, t 01 is the sampling time between two sampling points in the previous scene in the adjacent scene; S3112, using a preset second speed model, processing the interval between two sampling points in the next scene in the adjacent scene and the sampling time between the two sampling points to obtain a speed v2 of the next scene in the adjacent scene; The preset second speed model is: Where d2 is the interval between two sampling points in the next scene in the adjacent scene, t 02 is the sampling time between two sampling points in the next scene in the adjacent scene.

5. The multipath birth and death modeling method according to claim 3, characterized in that: The processing of the velocity v1 of the preceding scene and the velocity v2 of the succeeding scene in any two phase-continuous adjacent scenes to obtain the half-wavelength sampling density ρ1 of the preceding scene and the half-wavelength sampling density ρ2 of the succeeding scene in any two phase-continuous adjacent scenes comprises: S3121, using the first half-wavelength sampling density calculation model, processing the velocity v1 of the previous scene in the adjacent scene to obtain the half-wavelength sampling density ρ1 of the previous scene in the adjacent scene; The first half-wavelength sampling density calculation model is: In the formula, F s is the baseband sampling rate, c is the speed of light, f center is the center frequency; S3122, using a second half-wavelength sampling density calculation model, processing the velocity v2 of the next scene in the adjacent scenes to obtain a half-wavelength sampling density ρ2 of the next scene in the adjacent scenes; The second half-wavelength sampling density calculation model is: In the formula, F s is the baseband sampling rate, c is the speed of light, f center is the center frequency.

6. A multipath birth and death modeling device, characterized in that: The device comprises: The multipath quantity processing module is used to perform multipath quantity processing on M adjacent scenes to obtain M adjacent scenes with the same multipath quantity, where M is a positive integer and includes: S11, obtaining the number of multipaths of M adjacent scenes; S12, processing the multipath numbers of the M adjacent scenes to find the maximum multipath number N max,path ; S13, according to the maximum multipath number N max,path , performing multipath quantity processing on the M adjacent scenes to obtain M adjacent scenes having the same multipath quantity; A phase processing module, used to perform phase processing on the M adjacent scenes having the same number of multipaths to obtain M adjacent scenes with continuous phases, includes: S21, performing impulse response calculation on the M adjacent scenes having the same number of multipaths to obtain M adjacent scene impulse responses; S22, processing the M adjacent scene impulse responses to obtain M adjacent scenes with continuous phases; The multipath generation and death module is used to process the M adjacent scenes with continuous phases to achieve multipath generation and death between scenes with different speeds, including: S31, processing any two phase-continuous adjacent scenes to obtain a half-wavelength sampling density ρ1 of a preceding scene and a half-wavelength sampling density ρ2 of a succeeding scene in the any two phase-continuous adjacent scenes; S32, performing multipath splicing on the arbitrary two phase-continuous adjacent scenes according to the half-wavelength sampling density ρ1 of the previous scene and the half-wavelength sampling density ρ2 of the subsequent scene, so as to realize multipath generation and death between scenes with different speeds.

7. A multipath birth and death modeling device, characterized in that: The device comprises: A memory storing executable program code; a processor coupled to the memory; The processor calls the executable program code stored in the memory to execute the multipath birth and death modeling method according to any one of claims 1 to 5.

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