A signal modulation system, method, and transmitter

Abstract

The application discloses a signal modulation system, method and transmitter, which is used for calculating the zero-crossing point position information of a radio frequency signal at a low digital sampling rate, and realizing the modulation of an IQ signal by a polar coordinate transmitter. The system comprises a phase-locked loop module, a digital front-end processing module and a signal modulation module. The phase-locked loop module is used for providing a local oscillator signal for the signal modulation module. The digital front-end processing module is used for obtaining a complex baseband signal, performing up-sampling on the complex baseband signal, determining a target time at which the phase of the up-sampled complex baseband signal is a preset phase, and determining a modulation signal based on the target time, and sending the modulation signal to the signal modulation module. The sampling rate of the up-sampled complex baseband signal is N times of the sampling rate before the up-sampling, and N is less than a preset threshold. The signal modulation module is used for generating a modulated radio frequency signal based on the local oscillator signal and the modulation signal.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a signal modulation system, method, and transmitter. Background Technology

[0002] Polar transmitters, with their advantage of efficiently utilizing radio frequency power, have become a key technology in modern wireless systems. In the modulation methods of polar transmitters, adjusting the amplitude and phase of the carrier signal typically requires combining the zero-crossing position information of the carrier signal. However, current zero-crossing determination and compensation schemes, when implemented in the digital domain, require a digital sampling rate thousands of times higher than that of the local oscillator (LO), making it difficult to achieve a certain modulation accuracy.

[0003] Therefore, there is an urgent need for a signal modulation method to calculate the zero-crossing position information of radio frequency signals at a lower digital sampling rate, so as to realize the modulation of IQ signals by polar coordinate transmitters. Summary of the Invention

[0004] This application provides a signal modulation system, method, and transmitter for calculating the zero-crossing position information of a radio frequency signal at a low digital sampling rate, thereby enabling the modulation of IQ signals by a polar coordinate transmitter.

[0005] In a first aspect, embodiments of this application provide a signal modulation system, the system comprising: a phase-locked loop module, a digital front-end processing module, and a signal modulation module, wherein...

[0006] The phase-locked loop module is used to provide a local oscillator signal to the signal modulation module;

[0007] The digital front-end processing module is used to acquire a complex baseband signal, upsample the complex baseband signal, determine the phase of the upsampled complex baseband signal as a target time of a preset phase, determine a modulation signal based on the target time, and send the modulation signal to the signal modulation module. The upsampled sampling rate of the complex baseband signal is N times that before sampling, where N is less than a preset threshold.

[0008] The signal modulation module is used to generate a modulated radio frequency signal based on the local oscillator signal and the modulation signal.

[0009] As an optional implementation, the digital front-end processing module includes: a signal rate converter module, a coordinate transformation calculation module, a zero-crossing time calculation module, and a modulation signal calculation module, wherein...

[0010] The signal rate converter module is used to upsample the complex baseband signal to obtain the upsampled complex baseband signal;

[0011] The coordinate transformation calculation module is used to separate the amplitude signal and the phase signal from the upsampled complex baseband signal;

[0012] The zero-crossing time calculation module is used to determine the target time when the phase of the phase signal is the preset phase;

[0013] The modulation signal calculation module is used to determine the modulation signal based on the amplitude signal and the target time.

[0014] As an optional implementation, the zero-crossing time calculation module is specifically used for:

[0015] Determine the phase value of the phase signal at multiple discrete moments;

[0016] Linear interpolation is performed on the phase values ​​at the multiple discrete time points to determine the phase curve after linear interpolation;

[0017] The reference time for determining the phase value of the preset phase in the phase curve;

[0018] The reference time is represented by an unsigned number with a preset number of bits in a fixed-point representation to obtain the target time in the digital domain.

[0019] As an optional implementation, the modulation signal includes a phase modulation signal and an amplitude modulation signal;

[0020] The modulation signal calculation module includes: a zero-crossing amplitude calculation module and a forward differential module, wherein,

[0021] The zero-crossing amplitude calculation module is used to determine the amplitude modulation signal based on the amplitude signal and the target time;

[0022] The forward differential module is used to perform forward differential operations on the target time to obtain the phase modulation signal.

[0023] As an optional implementation, the zero-crossing amplitude calculation module is specifically used for:

[0024] For the first target time, calculate the linear interpolation result between the amplitude of the first target time and the amplitude of the previous target time to obtain multiple linear interpolation results;

[0025] The obtained linear interpolation results are determined as the amplitude modulation signal.

[0026] As an optional implementation, the signal modulation module includes a digital-to-time converter module and a power amplifier module, wherein,

[0027] The digital-to-time converter module is used to generate a phase-modulated constant envelope signal based on the local oscillator signal and the phase modulation signal, and send the constant envelope signal to the power amplifier module;

[0028] The power amplifier module is used to generate an amplitude-modulated radio frequency signal based on the amplitude modulation signal and the constant envelope signal.

[0029] As an optional implementation, the digital front-end processing module is a complex programmable logic device or a programmable gate array.

[0030] Secondly, embodiments of this application provide a polar coordinate transmitter, including a receiver, a transmitter, and a signal modulation system provided in the first aspect of this application. The signal modulation system is used to modulate a complex baseband signal received by the receiver into a radio frequency signal and to transmit the radio frequency signal by the transmitter.

[0031] Thirdly, embodiments of this application provide a signal modulation method, the method comprising:

[0032] Acquire complex baseband signal;

[0033] The complex baseband signal is upsampled to determine the target time when the phase of the upsampled complex baseband signal is a preset phase, and the modulation signal is determined based on the target time. The sampling rate of the upsampled complex baseband signal is N times that of the complex baseband signal, where N is less than a preset threshold.

[0034] Based on the modulation signal and the pre-acquired local oscillator signal, a modulated radio frequency signal is generated.

[0035] As an optional implementation, determining the target time when the phase of the upsampled complex baseband signal is the preset phase, and determining the modulation signal based on the target time, includes:

[0036] Separate the amplitude signal and the phase signal from the upsampled complex baseband signal;

[0037] The target time when the phase of the phase signal is determined to be the preset phase;

[0038] The modulation signal is determined based on the amplitude signal and the target time.

[0039] As an optional implementation, determining the target time when the phase of the phase signal is the preset phase includes:

[0040] Determine the phase value of the phase signal at multiple discrete moments;

[0041] Linear interpolation is performed on the phase values ​​at the multiple discrete time points to determine the phase curve after linear interpolation;

[0042] The reference time for determining the phase value of the preset phase in the phase curve;

[0043] The reference time is represented by an unsigned number with a preset number of bits in a fixed-point representation to obtain the target time in the digital domain.

[0044] As an optional implementation, the modulation signal includes a phase modulation signal and an amplitude modulation signal;

[0045] Determining the modulation signal based on the amplitude signal and the target time includes:

[0046] Based on the amplitude signal and the target time, the amplitude modulation signal is determined;

[0047] The phase modulation signal is obtained by performing a forward differential operation on the target time.

[0048] As an optional implementation, determining the amplitude modulation signal based on the amplitude signal and the target time includes:

[0049] For the first target time, calculate the linear interpolation result between the amplitude of the first target time and the amplitude of the previous target time to obtain multiple linear interpolation results;

[0050] The obtained linear interpolation results are determined as the amplitude modulation signal.

[0051] As an optional implementation, generating the modulated radio frequency signal based on the modulated signal and the pre-acquired local oscillator signal includes:

[0052] Based on the phase modulation signal and the pre-acquired local oscillator signal, a phase-modulated constant envelope signal is generated;

[0053] An amplitude-modulated radio frequency signal is generated based on the amplitude modulation signal and the constant envelope signal.

[0054] Fourthly, embodiments of this application provide a signal modulation apparatus, the apparatus comprising:

[0055] Acquisition unit, used to acquire complex baseband signal;

[0056] The processing unit is configured to upsample the complex baseband signal, determine the target time when the phase of the upsampled complex baseband signal is a preset phase, and determine the modulation signal based on the target time, wherein the sampling rate of the upsampled complex baseband signal is N times that of the complex baseband signal, and N is less than a preset threshold.

[0057] A modulation unit is used to generate a modulated radio frequency signal based on the modulation signal and a pre-acquired local oscillator signal.

[0058] As an optional implementation, the processing unit is specifically used for:

[0059] Separate the amplitude signal and the phase signal from the upsampled complex baseband signal;

[0060] The target time when the phase of the phase signal is determined to be the preset phase;

[0061] The modulation signal is determined based on the amplitude signal and the target time.

[0062] As an optional implementation, the processing unit is specifically used for:

[0063] Determine the phase value of the phase signal at multiple discrete moments;

[0064] Linear interpolation is performed on the phase values ​​at the multiple discrete time points to determine the phase curve after linear interpolation;

[0065] The reference time for determining the phase value of the preset phase in the phase curve;

[0066] The reference time is represented by an unsigned number with a preset number of bits in a fixed-point representation to obtain the target time in the digital domain.

[0067] As an optional implementation, the modulation signal includes a phase modulation signal and an amplitude modulation signal;

[0068] The processing unit is specifically used for:

[0069] Based on the amplitude signal and the target time, the amplitude modulation signal is determined;

[0070] The phase modulation signal is obtained by performing a forward differential operation on the target time.

[0071] As an optional implementation, the processing unit is specifically used for:

[0072] For the first target time, calculate the linear interpolation result between the amplitude of the first target time and the amplitude of the previous target time to obtain multiple linear interpolation results;

[0073] The obtained linear interpolation results are determined as the amplitude modulation signal.

[0074] As an optional implementation, the modulation unit is specifically used for:

[0075] Based on the phase modulation signal and the pre-acquired local oscillator signal, a phase-modulated constant envelope signal is generated;

[0076] An amplitude-modulated radio frequency signal is generated based on the amplitude modulation signal and the constant envelope signal.

[0077] Fifthly, embodiments of this application provide a signal modulation apparatus, the apparatus including a processor and a memory, the memory being used to store a program executable by the processor, the processor being used to read the program in the memory and execute the method described in any one of the third aspects.

[0078] In a sixth aspect, embodiments of this application also provide a computer storage medium having a computer program stored thereon, which, when executed by a processor, is used to implement the steps of the method described in the third aspect above.

[0079] In a seventh aspect, this application provides a computer program product comprising: computer program code, which, when run on a computer, causes the computer to perform the method described in any one of the third aspects.

[0080] The beneficial effects of the embodiments of this application are as follows:

[0081] This application provides a signal modulation system, method, and transmitter. By upsampling the acquired complex baseband signal, the target time when the phase of the upsampled complex baseband signal is a preset phase is determined. The modulation signal is then determined based on the determined target time. Finally, a modulated radio frequency signal is generated based on the local oscillator signal and the modulation signal. The sampling rate of the upsampled complex baseband signal is N times that before sampling, where N is less than a preset threshold. This method can calculate the target time when the phase of the upsampled complex baseband signal is a preset phase at a digital sampling rate several times that of the complex baseband signal. This target time is the zero-crossing time of the radio frequency signal, that is, the zero-crossing position information of the radio frequency signal is calculated at a lower digital sampling rate, thereby realizing the modulation of the IQ signal by the polar coordinate transmitter.

[0082] These or other aspects of this application will become more apparent in the following description of embodiments. Attached Figure Description

[0083] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0084] Figure 1 This is a schematic diagram of a signal modulation system provided in an embodiment of this application;

[0085] Figure 2 A schematic diagram of the structure of a digital front-end processing module provided in an embodiment of this application;

[0086] Figure 3 This is a schematic diagram of the structure of another digital front-end processing module provided in an embodiment of this application;

[0087] Figure 4 This is a schematic diagram of another signal modulation system provided in an embodiment of this application;

[0088] Figure 5 A schematic diagram of the structure of another digital front-end processing module provided in an embodiment of this application;

[0089] Figure 6 A schematic flowchart illustrating a signal modulation method provided in an embodiment of this application;

[0090] Figure 7 This is a schematic diagram of the structure of a signal modulation device provided in an embodiment of this application;

[0091] Figure 8 This is a schematic diagram of a signal modulation device provided in an embodiment of this application. Detailed Implementation

[0092] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0093] In the embodiments of this application, the term "and / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. The character " / " generally indicates that the preceding and following associated objects have an "or" relationship.

[0094] The application scenarios described in this application are for the purpose of more clearly illustrating the technical solutions of this application, and do not constitute a limitation on the technical solutions provided in this application. Those skilled in the art will understand that with the emergence of new application scenarios, the technical solutions provided in this application are also applicable to similar technical problems. In the description of this application, unless otherwise stated, "multiple" means two or more.

[0095] Before introducing the signal modulation scheme provided in the embodiments of this application, the technical background of the embodiments of this application will be described in detail below for ease of understanding.

[0096] Polar transmitters, with their advantage of efficiently utilizing radio frequency power, have become a key technology in modern wireless systems. When processing signals, they typically need to decompose the IQ signal in the Cartesian coordinate system into amplitude and phase signals.

[0097] Specifically, the radio frequency real signal after quadrature modulation of the IQ signals is as shown in the following formula (1):

[0098]

[0099] Where, ω c =2πf c For radio frequency angular frequency, complex baseband signal:

[0100] The above formula (1) can be converted into the following formula (2), which is the radio frequency real signal output by the polar coordinate transmitter after modulating the IQ signal.

[0101]

[0102] Among them, the discrete-time radio frequency real signal in formula (2) is shown in formula (3).

[0103]

[0104] A polar coordinate transmitter is a device that implements the above formulas (2) and (3) in the analog or digital domain, requiring the carrier signal cos[ω] to be processed separately. c The amplitude and phase of [t] are adjusted by multiplying the amplitude of the carrier signal by A(t) and adjusting the instantaneous phase ω. c t plus the phase of the baseband signal

[0105] In the modulation method of a polar coordinate transmitter, when modulating the carrier signal cos[ω] c When adjusting the amplitude and phase of t], it is usually necessary to combine it with the carrier signal. The zero-crossing position information is obtained, but the current zero-crossing point acquisition and compensation schemes require a digital sampling rate thousands of times that of the local oscillator (LO) signal when implemented in the digital domain, making it difficult to achieve a certain modulation accuracy.

[0106] Therefore, there is an urgent need for a signal modulation method to calculate the zero-crossing position information of radio frequency signals at a lower digital sampling rate, so as to realize the modulation of IQ signals by polar coordinate transmitters.

[0107] In view of this, the signal modulation system, method, and transmitter provided in this application upsample the acquired complex baseband signal to determine the target time when the phase of the upsampled complex baseband signal is a preset phase, and further determine the modulation signal based on the determined target time. Finally, based on the local oscillator signal and the modulation signal, a modulated radio frequency signal is generated. The sampling rate of the upsampled complex baseband signal is N times that before sampling, where N is less than a preset threshold. This method can calculate the target time when the phase of the upsampled complex baseband signal is a preset phase at a digital sampling rate several times that of the complex baseband signal. This target time is the zero-crossing time of the radio frequency signal, that is, the zero-crossing position information of the radio frequency signal is calculated with a lower digital sampling rate, thereby realizing the modulation of the IQ signal by the polar coordinate transmitter.

[0108] After introducing the technical background of the embodiments of this application, the signal modulation scheme provided by the embodiments of this application will be described in detail below with reference to specific embodiments.

[0109] like Figure 1 As shown, the signal modulation system 10 provided in this application embodiment has a system architecture including: a phase-locked loop module 11, a digital front-end processing module 12, and a signal modulation module 13.

[0110] Phase-locked loop module 11 is used to provide local oscillator signal to signal modulation module 13.

[0111] In specific implementation, the phase-locked loop module 11 provides the signal modulation module 13 with a frequency of f LO In addition to the local oscillator signal, it can also provide a clock signal for the digital front-end processing module 12. For example, it can provide a clock signal for the digital front-end processing module 12 with a frequency of [frequency value missing]. A digital clock.

[0112] The digital front-end processing module 12 is used to acquire the complex baseband signal, upsample the complex baseband signal, determine the target time of the phase of the upsampled complex baseband signal as the preset phase, determine the modulation signal based on the target time, and send the modulation signal to the signal modulation module 13.

[0113] Among them, the complex baseband signal: The preset phase can be calculated based on the zero-crossing phase of the radio frequency (RF) signal. Specifically, the zero-crossing phase of the RF signal is an integer multiple of π, denoted as kπ, where k is a natural number. The phase of the RF signal is... in, To determine the phase of the upsampled complex baseband signal, the preset phase can be... n is a discrete time or discrete time point. At each discrete time n, the preset phase can have different phase values.

[0114] The sampling rate of the complex baseband signal after upsampling is N times that before sampling. The value of N can usually be 4, 8, 16, etc. N is less than a preset threshold. The preset threshold can be set according to experience, for example, the value of the preset threshold can be 50, 60 or 100.

[0115] The signal modulation module 13 is used to generate a modulated radio frequency signal based on the local oscillator signal and the modulation signal.

[0116] In specific implementation, such as Figure 2 As shown, the digital front-end processing module 12 can be further subdivided into: signal rate converter module 121, coordinate transformation calculation module 122, zero-crossing time calculation module 123, and modulation signal calculation module 124.

[0117] The signal rate converter module 121 is used to upsample the complex baseband signal to obtain the upsampled complex baseband signal.

[0118] In practical implementation, the signal rate converter module 121 can increase the sampling rate of the complex baseband signal from... Upsampled to f s The upsampling rate, i.e., the upsampling rate of the complex baseband signal, is N times the original sampling rate. The value of N can usually be 4, 8, or 16.

[0119] In a specific implementation, the signal rate converter module 121 can be composed of a multi-stage half-band filter, a Farrow filter, and a fractional delay filter. The specific structure of this application embodiment is not limited.

[0120] The coordinate transformation calculation module 122 is used to separate the amplitude signal and the phase signal from the upsampled complex baseband signal.

[0121] In practice, the coordinate transformation calculation module 122 can convert the upsampled complex baseband signal (IQ signal) into an amplitude signal A and a phase signal. For example, it can be specifically implemented using the Coordinate Rotation Digital Computer (CORDIC) algorithm.

[0122] The zero-crossing time calculation module 123 is used to determine the target time when the phase of the phase signal is the preset phase.

[0123] In some implementations, when specifically determining the target time where the phase of the phase signal is a preset phase, the phase values ​​of the phase signal at multiple discrete moments are first determined. Linear interpolation is then performed on the phase values ​​at these discrete moments to determine the linearly interpolated phase curve. Next, a reference time with a preset phase value is determined from the phase curve, and this reference time is represented using a preset-bit unsigned number in a fixed-point format to obtain the target time in the digital domain. The preset phase is... The preset phase can have different phase values.

[0124] In other embodiments, when specifically determining the target time where the phase of the phase signal is the preset phase, it can also be calculated using the instantaneous phase of the radio frequency signal output by the modulation system under ideal conditions. In the embodiments of this application, the radio frequency signal output by the modulation system under ideal conditions is...

[0125] Specifically, firstly, based on the phase signal, the instantaneous phase of the radio frequency signal is determined. Then, linear interpolation is performed on the instantaneous phase at multiple discrete moments to determine the instantaneous phase curve after linear interpolation. Based on the instantaneous phase curve, the zero-crossing time of the instantaneous phase curve is determined. Finally, the zero-crossing time is represented by an unsigned number with a preset number of bits in a fixed-point representation to obtain the zero-crossing time of the radio frequency signal in the digital domain, which is also the target time.

[0126] The linear interpolation can be performed using methods found in related technologies, and this application does not limit the specific methods used in this embodiment.

[0127] Specifically, the instantaneous phase of the radio frequency signal is shown in the following formula (4):

[0128]

[0129] Where n is a discrete time point or discrete moment, and the phase increment is fixed. Phase signal is

[0130]

[0131] The instantaneous phase curve after linear interpolation can be expressed as the following formula (5):

[0132]

[0133] in, For the forward difference of the phase, Let Φ(n) be the residual phase modulo π at time n, i.e.

[0134] Let ψ(t) = kπ to calculate the time t at the zero-crossing point. k As shown in formula (6) below:

[0135]

[0136] It should be noted that the number of zero-crossing moments between adjacent discrete time points may not be the same. For example, the number of zero-crossing moments between the 0th and 1st discrete time points is 1, the number of zero-crossing moments between the 1st and 2nd discrete time points is 2, and the number of zero-crossing moments between the 2nd and 3rd discrete time points is 2. Therefore, in the above formula (6), k is the zero-crossing index, k = 1, 2, ..., K(n), with a total of K(n) zero-crossing moments. The calculation method for the number of zero-crossing moments between two adjacent discrete time points is shown in formula (7):

[0137]

[0138] In specific implementation, to achieve this in the digital domain, the embodiments of this application also need to describe the above calculation results in a fixed-point representation in the digital domain. The following is a fixed-point description of digital signal processing, assuming it is of the form X. fix The quantities with the subscript 'fix' are all fixed-point representations of digital signals.

[0139] 2π fixed-point representation is 2π fix =2 m .

[0140] Fixed phase increment Fixed-point representation as in, For the integer part, The fractional part can be implemented by accumulating Q modulo P.

[0141] The forward difference of the phase is divided into Fixed-point representation as Residual phase Fixed-point representation as

[0142] The number of zero-crossing moments K(n) is expressed in fixed-point form as follows:

[0143] At the zero-crossing point, the unsigned fixed-point representation using q bits is as follows:

[0144]

[0145] in, This refers to the target time in the digital domain.

[0146] The modulation signal calculation module 124 is used to determine the modulation signal based on the amplitude signal and the target time.

[0147] In practical implementation, the modulation signal includes a phase modulation signal and an amplitude modulation signal, such as... Figure 3 As shown, the modulation signal calculation module 124 can be further subdivided into a zero-crossing amplitude calculation module 1241 and a forward differential module 1242.

[0148] The zero-crossing amplitude calculation module 1241 is used to determine the amplitude modulation signal based on the amplitude signal and the target time.

[0149] Specifically, based on the amplitude signal and the target time, when determining the amplitude modulation signal, for the first target time, the linear interpolation result between the amplitude at the first target time and the amplitude at the previous target time is calculated to obtain the linear interpolation result A for each target time. The multiple linear interpolation results obtained are then used as the amplitude modulation signal. Here, the first target time can be any target time.

[0150] For the first target time, the amplitude modulation signal A1(n) can be expressed as:

[0151]

[0152] For the target time k to K(n), the amplitude modulation signal can be expressed as:

[0153]

[0154] The forward differential module 1242 is used to perform forward differential operations on the target time to obtain the phase modulation signal.

[0155] In practice, the target time Perform forward differential operation, the result of which is a phase-modulated signal, where dp represents the phase-modulated signal at each target time.

[0156] For the first target time:

[0157]

[0158] For the 2nd to K(n)th target time points:

[0159] In practical applications, after determining the amplitude modulation signal and the phase modulation signal, the modulated radio frequency signal can be generated based on the local oscillator signal and the modulation signal. That is, the modulated radio frequency signal can be generated based on the local oscillator signal, the amplitude modulation signal and the phase modulation signal.

[0160] In specific implementation, such as Figure 4 As shown, the signal modulation module 13 can be further subdivided into a digital-to-time converter module 131 and a power amplifier module 132.

[0161] In this case, the phase-locked loop module 11 provides the local oscillator signal to the digital-to-time converter module 131, the digital front-end processing module 12 sends the phase modulation signal to the digital-to-time converter module 131, and sends the amplitude modulation signal to the power amplifier module 132.

[0162] Digital-to-time converter module 131 is used to generate a phase-modulated constant envelope signal based on the local oscillator signal and the phase-modulated signal. The constant envelope signal is then sent to the power amplifier module 132. The power amplifier module 132 is used to generate an amplitude-modulated radio frequency signal based on the amplitude modulation signal and the constant envelope signal.

[0163] It should be noted that the digital-to-time converter module 131 and the power amplifier module 132 can adopt existing designs, and this application embodiment does not specifically limit them.

[0164] In practical applications, the digital front-end processing module 12 can be implemented using complex programmable logic devices or programmable logic gate arrays, or it can be implemented using hardware circuits.

[0165] In one example, such as Figure 5 As shown, when the digital front-end processing module 12 is implemented through a fixed circuit, it may include a phase forward differential calculation circuit 51, a residual phase calculation circuit 52, a zero-crossing time count calculation circuit 53, a zero-crossing time calculation circuit 54, a forward differential circuit 55, and a zero-crossing amplitude calculation circuit 56. Specifically, the phase forward differential calculation circuit 51 and the residual phase calculation circuit 52 are used to determine the instantaneous phase curve; the zero-crossing time count calculation circuit 53 is used to calculate the number of zero-crossing times; the zero-crossing time calculation circuit 54 is used to calculate the specific zero-crossing times; the forward differential circuit 55 is used to perform forward differential operations on the zero-crossing times to obtain the phase modulation signal; and the zero-crossing amplitude calculation circuit 56 is used to determine the amplitude modulation signal based on the amplitude signal and the zero-crossing times. Each circuit can be implemented using corresponding logic circuits, and this embodiment does not limit this.

[0166] Based on the same inventive concept, this application provides a polar coordinate transmitter, including a receiver, a transmitter, and a signal modulation system provided in this application. The signal modulation system is used to modulate the complex baseband signal received by the receiver into a radio frequency signal and to transmit the radio frequency signal by the transmitter.

[0167] Based on the same inventive concept, such as Figure 6 As shown in the figure, this application provides a signal modulation method, the specific implementation process of which includes:

[0168] Step 601: Obtain the complex baseband signal.

[0169] Step 602: Upsample the complex baseband signal, determine the target time of the phase of the upsampled complex baseband signal as the preset phase, and determine the modulation signal based on the target time. The sampling rate of the upsampled complex baseband signal is N times that before sampling, where N is less than a preset threshold.

[0170] Step 603: Generate a modulated radio frequency signal based on the modulated signal and the pre-acquired local oscillator signal.

[0171] As an optional implementation, determining the target time of the upsampled complex baseband signal phase as a preset phase, and determining the modulation signal based on the target time, includes:

[0172] Separate the amplitude signal and the phase signal from the upsampled complex baseband signal;

[0173] Determine the target time when the phase of the phase signal is the preset phase;

[0174] The modulation signal is determined based on the amplitude signal and the target time.

[0175] As an optional implementation, determining the target time when the phase of the phase signal is a preset phase includes:

[0176] Determine the phase value of the phase signal at multiple discrete moments;

[0177] Linear interpolation is performed on the phase values ​​at multiple discrete time points to determine the phase curve after linear interpolation;

[0178] Determine the reference time in the phase curve where the phase value is the preset phase;

[0179] The reference time is represented by an unsigned number with a preset number of bits in a fixed-point format, and the target time in the digital field is obtained.

[0180] As an optional implementation, the modulation signal includes a phase modulation signal and an amplitude modulation signal;

[0181] Based on the amplitude signal and the target time, the modulation signal is determined, including:

[0182] Determine the amplitude modulation signal based on the amplitude signal and the target time;

[0183] A forward differential operation is performed on the target time to obtain the phase modulation signal.

[0184] As an optional implementation, determining the amplitude modulation signal based on the amplitude signal and the target time includes:

[0185] For the first target time, calculate the linear interpolation result between the amplitude at the first target time and the amplitude at the previous target time, and obtain multiple linear interpolation results;

[0186] The obtained linear interpolation results are used as amplitude modulation signals.

[0187] As an optional implementation, a modulated radio frequency signal is generated based on the modulated signal and a pre-acquired local oscillator signal, including:

[0188] Based on the phase modulation signal and the pre-acquired local oscillator signal, a phase-modulated constant envelope signal is generated;

[0189] An amplitude-modulated radio frequency signal is generated based on the amplitude-modulated signal and the constant envelope signal.

[0190] Based on the same inventive concept, such as Figure 7 As shown in the figure, this application provides a signal modulation apparatus, the apparatus including:

[0191] Acquisition unit 701 is used to acquire complex baseband signals;

[0192] The processing unit 702 is used to upsample the complex baseband signal, determine the target time when the phase of the upsampled complex baseband signal is a preset phase, and determine the modulation signal based on the target time. The sampling rate of the upsampled complex baseband signal is N times that before sampling, and N is less than a preset threshold.

[0193] The modulation unit 703 is used to generate a modulated radio frequency signal based on the modulation signal and the pre-acquired local oscillator signal.

[0194] As an optional implementation, the processing unit 702 is specifically used for:

[0195] Separate the amplitude signal and the phase signal from the upsampled complex baseband signal;

[0196] Determine the target time when the phase of the phase signal is the preset phase;

[0197] The modulation signal is determined based on the amplitude signal and the target time.

[0198] As an optional implementation, the processing unit 702 is specifically used for:

[0199] Determine the phase value of the phase signal at multiple discrete moments;

[0200] Linear interpolation is performed on the phase values ​​at multiple discrete time points to determine the phase curve after linear interpolation;

[0201] Determine the reference time in the phase curve where the phase value is the preset phase;

[0202] The reference time is represented by an unsigned number with a preset number of bits in a fixed-point format, and the target time in the digital field is obtained.

[0203] As an optional implementation, the modulation signal includes a phase modulation signal and an amplitude modulation signal;

[0204] Processing unit 702 is specifically used for:

[0205] Determine the amplitude modulation signal based on the amplitude signal and the target time;

[0206] A forward differential operation is performed on the target time to obtain the phase modulation signal.

[0207] As an optional implementation, the processing unit 702 is specifically used for:

[0208] For the first target time, calculate the linear interpolation result between the amplitude at the first target time and the amplitude at the previous target time, and obtain multiple linear interpolation results;

[0209] The obtained linear interpolation results are used as amplitude modulation signals.

[0210] As an optional implementation, the modulation unit 703 is specifically used for:

[0211] Based on the phase modulation signal and the pre-acquired local oscillator signal, a phase-modulated constant envelope signal is generated;

[0212] An amplitude-modulated radio frequency signal is generated based on the amplitude-modulated signal and the constant envelope signal.

[0213] Based on the same inventive concept, such as Figure 8 As shown in the illustration, this application also provides a signal modulation device, which includes a processor 800 and a memory 801. The memory 801 is used to store programs executable by the processor 800, and the processor 800 is used to read and execute the programs in the memory 801.

[0214] Acquire complex baseband signal;

[0215] The complex baseband signal is upsampled to determine the target time when the phase of the upsampled complex baseband signal is the preset phase, and the modulation signal is determined based on the target time. The sampling rate of the upsampled complex baseband signal is N times that before sampling, and N is less than a preset threshold.

[0216] Based on the modulation signal and the pre-acquired local oscillator signal, a modulated radio frequency signal is generated.

[0217] As an optional implementation, the processor 800 is specifically configured to execute:

[0218] Separate the amplitude signal and the phase signal from the upsampled complex baseband signal;

[0219] Based on the phase signal, determine the target time of the desired radio frequency signal in the digital domain;

[0220] The target time is determined to be the phase of the phase signal with the preset phase.

[0221] As an optional implementation, the processor 800 is specifically configured to execute:

[0222] Determine the phase value of the phase signal at multiple discrete moments;

[0223] Linear interpolation is performed on the phase values ​​at multiple discrete time points to determine the phase curve after linear interpolation;

[0224] Determine the reference time in the phase curve where the phase value is the preset phase;

[0225] The reference time is represented by an unsigned number with a preset number of bits in a fixed-point format, and the target time in the digital field is obtained.

[0226] As an optional implementation, the modulation signal includes a phase modulation signal and an amplitude modulation signal;

[0227] Processor 800 is specifically configured to execute:

[0228] Determine the amplitude modulation signal based on the amplitude signal and the target time;

[0229] A forward differential operation is performed on the target time to obtain the phase modulation signal.

[0230] As an optional implementation, the processor 800 is specifically configured to execute:

[0231] For the first target time, calculate the linear interpolation result between the amplitude at the first target time and the amplitude at the previous target time, and obtain multiple linear interpolation results;

[0232] The obtained linear interpolation results are used as amplitude modulation signals.

[0233] As an optional implementation, the processor 800 is specifically configured to execute:

[0234] Based on the phase modulation signal and the pre-acquired local oscillator signal, a phase-modulated constant envelope signal is generated;

[0235] An amplitude-modulated radio frequency signal is generated based on the amplitude-modulated signal and the constant envelope signal.

[0236] Based on the same inventive concept, this disclosure provides a computer storage medium comprising: computer program code, which, when executed on a computer, causes the computer to perform any of the signal modulation methods discussed above. Since the principle by which the computer storage medium solves the problem is similar to that of the signal modulation method, the implementation of the computer storage medium can be found in the implementation of the method, and repeated details will not be elaborated further.

[0237] In specific implementation, computer storage media can include: Universal Serial Bus Flash Drive (USB), portable hard drive, Read-Only Memory (ROM), Random Access Memory (RAM), magnetic disk or optical disk, and other storage media that can store program code.

[0238] Based on the same inventive concept, this disclosure also provides a computer program product, which includes computer program code that, when executed on a computer, causes the computer to perform any of the signal modulation methods discussed above. Since the principle by which the above-described computer program product solves the problem is similar to that of the signal modulation method, the implementation of the above-described computer program product can be referred to the implementation of the method, and repeated details will not be elaborated further.

[0239] Computer program products may employ any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0240] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0241] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 Devices that specify the functions in one or more boxes.

[0242] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including an instruction device, which is implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0243] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0244] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A signal modulation system, characterized in that, The system includes: a phase-locked loop module, a digital front-end processing module, and a signal modulation module, wherein... The phase-locked loop module is used to provide a local oscillator signal to the signal modulation module; The digital front-end processing module is used to acquire a complex baseband signal, upsample the complex baseband signal, determine the phase of the upsampled complex baseband signal as a target time of a preset phase, determine a modulation signal based on the target time, and send the modulation signal to the signal modulation module. The upsampled sampling rate of the complex baseband signal is N times that before sampling, where N is less than a preset threshold. The signal modulation module is used to generate a modulated radio frequency signal based on the local oscillator signal and the modulation signal.

2. The system according to claim 1, characterized in that, The digital front-end processing module includes: a signal rate converter module, a coordinate transformation calculation module, a zero-crossing time calculation module, and a modulation signal calculation module, wherein... The signal rate converter module is used to upsample the complex baseband signal to obtain the upsampled complex baseband signal; The coordinate transformation calculation module is used to separate the amplitude signal and the phase signal from the upsampled complex baseband signal; The zero-crossing time calculation module is used to determine the target time when the phase of the phase signal is the preset phase; The modulation signal calculation module is used to determine the modulation signal based on the amplitude signal and the target time.

3. The system according to claim 2, characterized in that, The zero-crossing time calculation module is specifically used for: Determine the phase value of the phase signal at multiple discrete moments; Linear interpolation is performed on the phase values ​​at the multiple discrete time points to determine the phase curve after linear interpolation; The reference time for determining the phase value of the preset phase in the phase curve; The reference time is represented by an unsigned number with a preset number of bits in a fixed-point representation to obtain the target time in the digital domain.

4. The system according to claim 2, characterized in that, The modulation signal includes a phase modulation signal and an amplitude modulation signal; The modulation signal calculation module includes: a zero-crossing amplitude calculation module and a forward differential module, wherein, The zero-crossing amplitude calculation module is used to determine the amplitude modulation signal based on the amplitude signal and the target time; The forward differential module is used to perform forward differential operations on the target time to obtain the phase modulation signal.

5. The system according to claim 4, characterized in that, The zero-crossing amplitude calculation module is specifically used for: For the first target time, calculate the linear interpolation result between the amplitude of the first target time and the amplitude of the previous target time to obtain multiple linear interpolation results; The obtained linear interpolation results are determined as the amplitude modulation signal.

6. The system according to claim 4, characterized in that, The signal modulation module includes a digital-to-time converter module and a power amplifier module, wherein, The digital-to-time converter module is used to generate a phase-modulated constant envelope signal based on the local oscillator signal and the phase modulation signal, and send the constant envelope signal to the power amplifier module; The power amplifier module is used to generate an amplitude-modulated radio frequency signal based on the amplitude modulation signal and the constant envelope signal.

7. The system according to any one of claims 1-6, characterized in that, The digital front-end processing module is a complex programmable logic device or a programmable logic gate array.

8. A transmitter, characterized in that, The device includes a receiver, a transmitter, and a signal modulation system according to any one of claims 1-7, wherein the signal modulation system is used to modulate a complex baseband signal received by the receiver into a radio frequency signal and to transmit the radio frequency signal by the transmitter.

9. A signal modulation method, characterized in that, The method includes: Acquire complex baseband signal; The complex baseband signal is upsampled to determine the target time when the phase of the upsampled complex baseband signal is a preset phase, and the modulation signal is determined based on the target time. The sampling rate of the upsampled complex baseband signal is N times that before sampling, and N is less than a preset threshold. Based on the modulation signal and the pre-acquired local oscillator signal, a modulated radio frequency signal is generated.

10. The method according to claim 9, characterized in that, The step of determining the target time when the phase of the upsampled complex baseband signal is the preset phase, and determining the modulation signal based on the target time, includes: Separate the amplitude signal and the phase signal from the upsampled complex baseband signal; The target time when the phase of the phase signal is determined to be the preset phase; The modulation signal is determined based on the amplitude signal and the target time.

11. The method according to claim 10, characterized in that, The step of determining the target time when the phase of the phase signal is the preset phase includes: Determine the phase value of the phase signal at multiple discrete moments; Linear interpolation is performed on the phase values ​​at the multiple discrete time points to determine the phase curve after linear interpolation; The reference time for determining the phase value of the preset phase in the phase curve; The reference time is represented by an unsigned number with a preset number of bits in a fixed-point representation to obtain the target time in the digital domain.

12. The method according to claim 10, characterized in that, The modulation signal includes a phase modulation signal and an amplitude modulation signal; Determining the modulation signal based on the amplitude signal and the target time includes: Based on the amplitude signal and the target time, the amplitude modulation signal is determined; The phase modulation signal is obtained by performing a forward differential operation on the target time.

13. The method according to claim 12, characterized in that, Determining the amplitude modulation signal based on the amplitude signal and the target time includes: For the first target time, calculate the linear interpolation result between the amplitude of the first target time and the amplitude of the previous target time to obtain multiple linear interpolation results; The obtained linear interpolation results are determined as the amplitude modulation signal.

14. The method according to claim 12, characterized in that, The process of generating a modulated radio frequency signal based on the modulated signal and the pre-acquired local oscillator signal includes: Based on the phase modulation signal and the pre-acquired local oscillator signal, a phase-modulated constant envelope signal is generated; An amplitude-modulated radio frequency signal is generated based on the amplitude modulation signal and the constant envelope signal.

15. A signal modulation device, characterized in that, The device includes a processor and a memory for storing a program executable by the processor, and the processor for reading the program from the memory and performing the steps of the method according to any one of claims 9-14.

16. A computer storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the method as described in any one of claims 9 to 14.

17. A computer program product, characterized in that, The computer program product includes: computer program code, which, when run on a computer, causes the computer to perform the steps of the method as described in any one of claims 9 to 14.

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