Method and arrangement for improving signal reception

Abstract

Method for improving the signal reception of a satellite navigation receiver (110), comprising the following steps: Receiving a composite satellite signal comprising a desired signal component and an interfering signal component; Converting the received composite satellite signal into a digital received composite signal; Receiving and delaying a first set of samples of the digital received composite signal, the delay of the first set of samples being based on the quotient of the sampling frequency of the composite satellite signal and the chip rate of the desired signal component; Generating an interfering signal estimate of the interfering signal component based on the first set of samples; and Combining the interfering signal estimate and a second sample belonging to a second set of samples to be eliminated.to remove the interfering signal component wholly or partially from the composite satellite signal, wherein the first group of samples was received before the sample belonging to the second group of samples, wherein the removal of the interfering signal component is independent of a spreading code rate of the desired signal component and maintains the undisturbed spreading edge characteristic of the desired signal component, and the sampling frequency is independent of the chip rate.

Description

Field of invention

[0001] This disclosure relates generally to communication signals and in particular to a method and arrangement for removing unwanted components from communication signals. background

[0002] Communication signals are often accompanied by interference. The presence of interference reduces the accuracy of communication between two devices. Therefore, eliminating or removing interference, such as a disruptive signal, from a communication signal allows a receiver to determine the content of that signal more accurately. overview

[0003] This document discloses exemplary methods and arrangements for improving signal reception. One exemplary method disclosed herein for improving the signal reception of a satellite navigation receiver comprises receiving a composite satellite signal comprising a desired signal component and an interfering signal component; converting the received composite satellite signal into a digital received composite signal; receiving a first set of samples of the digital received composite signal; generating an interfering signal estimate of the interfering signal component based on the first set of samples; and combining the interfering signal estimate with a second sample belonging to a second set of samples to be eliminated, in order to remove the interfering signal component wholly or partially from the composite satellite signal.wherein the first group of samples was received before the sample belonging to the second group of samples, the distance being substantially independent of a spreading code rate of the desired signal component and substantially maintaining the undisturbed spreading edge characteristic of the desired signal component. An exemplary arrangement disclosed herein comprises a receiver for receiving a composite satellite signal comprising a desired signal component and an interfering signal component, a converter for converting the received composite satellite signal into a digital received composite signal, and an interference suppressor for receiving a first group of samples of the digital received composite signal.for generating a disturbance signal estimate of the interfering signal component based on the first group of samples and for combining the disturbance signal estimate with a second sample belonging to a second group of samples to be eliminated in order to remove the interfering signal component wholly or partially from the composite satellite signal, wherein the first group of samples was received before the sample belonging to the second group of samples, wherein the removal is substantially independent of a spreading code rate of the desired signal component and substantially preserves the undisturbed spreading edge characteristic of the desired signal component.

[0004] An exemplary machine-readable medium is disclosed herein with machine-readable instructions which, when executed, cause a machine to receive a composite satellite signal comprising a desired signal component and an interfering signal component, to convert the received composite satellite signal into a digital received composite signal, to receive a first set of samples of the digital received composite signal, to generate an interfering signal estimate of the interfering signal component based on the first set of samples, to combine the interfering signal estimate with a second sample belonging to a second set of samples to be eliminated, in order to remove the interfering signal component wholly or partially from the composite satellite signal.wherein the first group of samples was received before the sample belonging to the second group of samples, wherein the distance is essentially independent of a spreading code rate of the desired signal component and substantially maintains the undisturbed spreading edge characteristic of the desired signal component. Brief description of the drawings

[0005] Fig. Figure 1 shows an example receiver in an example usage environment.

[0006] Fig. Figure 2 is a block diagram of an example receiver used to implement a section of the receiver. Fig. 1 is usable.

[0007] Fig. Figure 3 is a diagram of a first, exemplary disturbance rejection system, implemented by the exemplary receiver of the Fig. 1 and / or Fig. 2 can be implemented.

[0008] Fig. Figure 4 is a diagram of a second, exemplary disturbance rejection system, implemented by the exemplary receiver of the Fig. 1 and / or Fig. 2 can be implemented.

[0009] Fig. 5 is a diagram that shows the structure of the Fig. 5A– Fig. Figure 5D depicts an exemplary automatic profit control system, an exemplary analog-to-digital conversion system, and a monitoring and verification system that can be implemented by the exemplary receiver of the figures and / or 2.

[0010] Fig. 6 is a diagram that shows the structure of the Fig. 6A– Fig. 6B of an implementation of the first exemplary fault rejection system of the Fig. 3 depicts, which in conjunction with the exemplary systems of the Fig. 5 can be used.

[0011] Fig. Figure 7 is a flowchart that represents an exemplary process executable using machine-readable instructions to implement the exemplary fault suppressor of the Fig. 2 to implement.

[0012] Fig. Figure 8 is a block diagram of an example processor platform that can be used to illustrate the process of Fig. 7 and other procedures to carry out the exemplary recipient of the Fig. 1 and / or Fig. 2 to implement. Detailed description

[0013] Methods and arrangements for improving signal reception are disclosed herein. Exemplary methods disclosed herein include receiving a composite satellite signal containing a desired signal component and converting the received composite satellite signal into a digital receiving composite signal. Exemplary methods include taking a first set of samples of the received digital composite signal and generating a noise signal estimate of the interfering signal component based on the first set of samples.Exemplary methods further include combining the noise signal estimation and a second sample belonging to a second group of samples to remove the noise signal component wholly or partially from the composite satellite signal, wherein the first group of samples was received before the sample belonging to the second group of samples, the removal being essentially independent of a spreading code rate of the desired signal component and substantially preserving the undisturbed spreading edge characteristic of the desired signal component.

[0014] In some embodiments, generating the noise estimate involves weighted combining of the first sample group. Exemplary procedures further include updating the weights used in the weighted combining by a least-mean-squares method. In some examples, the least-mean-squares method updates the weights by integrating a correlation between the first group of samples and the combined noise estimate, and the sample belonging to the second group of samples.

[0015] In some examples, the first group of samples refers to a first communication chip, and the sample belonging to the second group refers to a second communication chip that differs from the first. In some examples, the second communication chip is at least one communication chip away from the first. In some examples, the first and second groups of samples are associated with a spread spectrum navigation system.

[0016] The Fig. Figure 1 shows an exemplary environment of use 100 for an exemplary recipient 110 , which is built according to the teachings of the present revelation to improve signal reception. In the example shown, the Fig. 1 is the exemplary recipient 110 in the presence of an exemplary base station 120, an example of a satellite 130 and an exemplary troublemaker 140 shown. The recipient 110 receives signals from the base stations 120 and / or the satellite 130 , as well as signals from the jammer 140 As described below, the receiver processes 110 received signals in a way that allows the unwanted effects of the signal from the interfering source to be eliminated. 140 to avoid.

[0017] In the example shown, the Fig. 1. The receiver is a receiver for a global navigation satellite system (GNSS). The receiver 110 is capable of communicating with the base station 120 and the satellite 130 to communicate. In some examples, the recipient 110 a mobile phone, a personal digital assistant (PDA), tablet computer and / or a similar mobile device.

[0018] The base station 120 the Fig. 1 can be connected to the recipient 110 communicate wirelessly to send it to the recipient 110 to enable connection to a network (e.g., the internet, a cell network, a local area network, etc.). In some examples, the base station provides 120 Signals ready for the receiver 110 to assist with navigation functions. In addition, the receiver can 110 with the base station 120 communicate for the purpose of updating software or other maintenance procedures. While in the Fig. 1 only a single base station 120 As shown, other base stations may be present and advantageous to the receiver. 110 used during navigation or other operations.

[0019] In the Fig. The example shown is the satellite. 130 A satellite connected to one or more spread-spectrum global navigation satellite systems (GNSS). The satellite130 It can, for example, be part of a Global Positioning System (GPS), Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS), Compass, Galileo, etc. The satellite 130 sends out signals that are received by the receiver 110 received and processed in order to deliver it to the recipient 110 (or additional ones, with the recipient 110 to facilitate the determination of the recipient's geographical location in communication systems) in communication systems. 110 to determine. In one example, the satellite represents 130 Geographic location data, such as time signals, communication signals, etc., for the receiver 110 in the form of spread-spectrum encoded signals. In the example shown, the receiver can 110 Receive signals from one or more GNSS systems and thus receive signals in a variety of spread spectrum code chip rates.

[0020] On the transmitting side of a spread-spectrum communication system, symbols, each of which can represent a number of bits of information, are combined with a pseudorandom (PN) chip sequence that has a chip rate higher than the symbol rate. The combination of symbols and chip sequence spreads the symbols across a range of a communication frequency spectrum. The spread-spectrum signal is then modulated and upconverted to a radio frequency signal and transmitted. On the receiving side, the received signal is downconverted, and the spread-spectrum signal is sampled at a sampling rate and combined with a chip sequence to obtain the symbols that were originally combined with the chip sequence at the transmitting side. The chip sequence is a pseudorandom sequence, and therefore neighboring chips are uncorrelated (i.e., they are not randomly generated).neighboring chips are uncorrelated) and information combined with neighboring chips (e.g. symbols) is uncorrelated.

[0021] The troublemaker 140 can be any electronic device (e.g., another communication device, microwave oven, transformer, power line, etc.) that is capable of transmitting the communication between the receiver 110 and the base station 120 or the satellite 130 to disturb. The disturber 140 It can be a narrowband jammer that interferes with communication signals from the satellite. 130 to the recipient 110 superimposed, whether intentionally or unintentionally, by emitting interference signals at or near the same frequency on which the communication signals are transmitted and / or received. Even though in the Fig. 1 only one interference 140 As depicted, multiple disruptors may be present.

[0022] In the example shown, according to Fig. 1. The recipient receives 110 Communication signals from the base station 120 and / or the satellite 130 and interfering signals from the interfering source 140 In the example shown, signals from the base station 120 and / or the satellite 130 desirable, while signals from the interfering source 140 are not desirable and impair the recipient's ability 110 reduce signals from the base stations 120 and / or the satellite 130 to receive the interfering signal. Thus, the interfering signal can be received from the source. 140 by the recipient 110 be removed as described below to improve the receiver's performance 110 upon receiving the intended communication signal from the base station 120 and / or from the satellite 130 to improve it. That means that the interfering signal is filtered out by the receiver. 110 It is improved to increase its performance.

[0023] The Fig. Figure 2 is a block diagram of a section of an example receiver, such as the receiver 110 the Fig. 1. To improve signal reception. For example, the Fig. 2. The receiver includes an antenna. 201 , which uses a low-noise amplifier 210 (LNA, English: low noise amplifier), an automatic gain control 220 (AGC, English: automatic gain control), an analog-to-digital converter (A / D) 230 , a interference suppressor 240 and a demodulator / decoder 250 is connected. Although in the representation according to Fig. The components of the two discrete structures shown can be identified. Fig. 2 can be combined in one or more integrated circuits. Also, some of the components of the circuit can be combined in the Fig. The second example shown may be omitted or changed.

[0024] The antenna 201receives signals, for example, from the base station 120 , the satellite 130 and / or the disruptor 140 the Fig. 1. In one example, the antenna couples 201 a composite signal to the amplifier 210 The composite signal can contain spreadband spectrum navigation signals from the satellite. 130 (e.g., a desired signal component) as well as a signal from the interfering source 140 (e.g., an unwanted interference signal component). In one example, the receiver might 110 The amplifier identifies and processes the desired signal component to perform geographic positioning or other navigation functions. 210 amplifies the composite signals from the antenna 201 , which may contain interfering signal components, and places these under gain control 220 ready. For example, the amplifier 210and / or the gain control 220 have functionality to receive the signal from the antenna 201 to convert down to an intermediate or fundamental band frequency. Alternatively, a separate low-conversion block can be provided.

[0025] The gain control 220 the Fig. 2 receives the amplified, composite satellite signals from the amplifier 210 and adjusts a gain applied to the composite signal so that the signal levels match the sensitivity range of the analog-to-digital converter. 230 fit together. The gain control 220 sets the receiver's amplification 110 so fixed that the amplitude of the received signal is essentially within the maximum permissible amplitude range of the analog-to-digital converter 230 without clipping. In some examples, the gain control detects 220Automatically detects sudden changes in signal strength using maximum and minimum thresholds. These sudden changes can be caused by the start or end of an interfering signal from the source of the interference. 140 This occurs because the interference signal strength would otherwise exceed the range of the analog-to-digital converter. 230 This could cause saturation, leading to truncation. The gain control 220 adjusts the receiver's gain 110 to compensate for the change, in order to provide it to the interference suppressor 240 to enable the identification and removal of the interfering or superimposed signal from the composite signal. The output of the gain control is fed to the analog-to-digital converter. 230 supplied.

[0026] In the example shown, the Fig. 2 sets the analog-to-digital converter 230 the Fig. 2 the composite, from the amplification control 220The received signal is converted into a digital composite signal. The digital composite signal can consist of one or more samples or groups of samples. In some examples, the sampling rate of the composite digital signal is 4, 16, or 24 times the oscillator frequency of the receiver. 110 , which can be 10.23 MHz. In one example, the chip rate, which is the rate at which the chips are combined with symbols to generate a spread spectrum signal, is 1.023 MHz. The analog-to-digital converter 230 sends the digital signal to the interference suppressor 240 An exemplary implementation of the amplification control 220 and the analog-to-digital converter 230 the Fig. 2 is referred to by reference to the Fig. 5 further described.

[0027] In the example shown, the Fig. 2 removes the interference suppressor 240the interfering signal component, such as interfering signals from the interfering source 140 , wholly or partially, which were received at or near the same frequency as the composite satellite signal. The interference suppressor 240 It performs an interference signal estimation, for example, the amplitude and phase of the interfering signal, based on an initial group of received samples. The interference suppressor 240 the Fig. 2 uses interference signal estimation to remove interference from the composite satellite signal. The interference suppressor 240 It then forwards the composite satellite signal, which is essentially free of interference (i.e., the desired satellite component), to the demodulator / decoder. 250 The demodulator / decoder 250 demodulates / decodes the composite satellite signal, which now essentially consists of the desired satellite signal component.

[0028] The diagrams of Fig. 2 to Fig. 6 and the flowchart of the Fig. 7 represent systems and processes that can be implemented using example hardware and / or machine-readable instructions stored on a touchable medium to control one or more of the amplifiers 210 , the reinforcement regulation 220 , of the analog-to-digital converter 230 , of the interference suppressor 240 and the demodulator / decoder 250 and / or more generally, the recipient's 110 to implement. For example, the systems and processes can be executed using machine-readable instructions, such as a program for execution by a processor, such as the processor. 812 , which is in the exemplary processor platform 800 is shown, which is related to the Fig. 8 is discussed below. Such a program can be embodied in software that is stored on a tangible storage medium such as memory, a CD-ROM, a floppy disk, a hard disk, a DVD, a Blu-ray disc, or a device connected to the processor. 812 The program is stored in the connected memory, however, the entire program or part of it could alternatively be stored in memory controlled by the processor. 812 different devices and / or are executed in and / or embodied in firmware or hardware. Although examples referencing the Fig. 3 to Fig. As described in section 7, many other techniques or procedures for implementing the receiver can be used. 110 and the processes and systems used within it. For example, the execution order of the blocks can be changed and / or some of the described blocks can be modified, removed, or combined.

[0029] As mentioned above, the exemplary systems and procedures described herein can be implemented using coded instructions (e.g., computer-readable instructions) stored on a tangible, computer-readable storage medium, such as a hard disk, flash memory, ROM, cache, RAM, and / or any other storage medium, in which information is stored for any duration (e.g., for extended periods, continuously, briefly, for temporary buffering, and / or caching of information). As used herein, the term tangible, computer-readable storage medium is expressly defined to include any type of computer-readable storage device and / or disk, excluding progressive signals.

[0030] Additionally or alternatively, the exemplary systems and processes described herein can be implemented using coded instructions (e.g., computer-readable instructions) stored on a non-transient computer-readable storage medium, such as a hard disk, flash memory, ROM, cache, RAM, and / or other storage medium, for any duration (e.g., for extended periods, continuously, briefly, for temporary buffering, and / or caching of information). As used herein, the term non-transient computer-readable medium is expressly defined to encompass any type of computer-readable storage disk or storage device and to exclude progressive signals. As used herein, when the phrase "at least" is used as a transitional term in a preamble of a claim, it is open-ended in the same way that the term "encompassing" is open-ended.Thus, a claim that uses "at least" as a transitional term in its preamble can include additional features beyond those expressly mentioned in the claim.

[0031] The diagram of Fig. 3 is representative of a system 300 , which can be used to suppress interference 240 the Fig. 2 to implement. As shown, the system receives 300 a sample 302 (E_IN) of a signal containing signal (S), interference or superposition (J), and noise (N) components. The system 300 generates an interference signal estimate (J), removes some or all of the interfering components J, and outputs a satellite signal component 306 (E_sig) out.

[0032] During the operation of the system 300 the Fig. 3 goes through the received sample 302 through two delay lines 310 , 320 The sample 302will be in the first delay line 310 buffered for a threshold number of samples, i.e., the sample must wait until the threshold number of samples has been processed before it enters the second delay line. 320 is being moved. The first delay line 310 ensures that the samples are in the second delay line 320 from a different chip than the sample 302 In some examples, the threshold number of samples is given as M, where M = F S / F CHIP , F S is equal to the sampling frequency and F CHIP is equal to the chip rate or time-multiplexed chip rate, e.g. 1.023 MHz.

[0033] The first delay line 310 enables the system 300Maintaining the correlation for an interfering signal, e.g., a noise signal, as described herein, is challenging because the interfering signal covers multiple chips and will therefore be correlated between the chips, even with a delay between samples, which means the samples are parts of different chips. However, the number of samples M in the delay is greater than one chip, which decorrelates the desired signal component, since sections of the desired signal components combined with different chips are not correlated. Thus, thanks to the first delay line... 310 The only components correlated between adjacent chips are the disturbances. Decorrelation is performed using the lowest chip rate of the satellite. 130 and / or the base station 120 created.

[0034] After waiting in the first delay line 310The sample moves into the second delay line 320 The second delay line 320 , which can be implemented using a delay line with a finite impulse response (FIR), stores a number of samples L. A block 330 The least common square mean analyzes one or more previously received and / or output signal(s) to determine L updating weights. 340 to determine which of the corresponding L samples of the second delay line 320 to be added together. The samples of the second delay line (including the example sample) 302 ) are updated with the updated weights 340 (e.g. w[0], w[1] ... w[L – 1]) combined before being put into the summing array 350 to be moved. The summator 350 adds the weighted samples from the second delay line 320 and provides a sample 355(E_LO) out. The sample 355 (E_LO) is a disturbance signal estimation (J), as described here, since the amplitude of the signal component S and the noise component N is compared with the J component of the samples in the second delay line. 320 are very small due to the decorrelation caused by the first delay line.

[0035] To reduce the interference component of the received sample 302 To identify and remove the received sample 302 in the block 360 combined with an exemplary disturbance signal estimation (e.g., the disturbance signal estimation J) to obtain a sample 365 (E_err) to obtain, which is based on previously received, in the second delay line 320 stored samples and through the block 330 The weightings are calculated using the least common square mean. The combined sample 365can be defined by E_err = S + N + δJ, where δJ equals J – J. In the example shown, the sample 365 (E_err) is used for demodulation processing and detects a discontinuity of an interference signal (e.g., an interference waveform from the interfering source). 140 ) leads to an inaccurate estimate of J of the received sample 302 , which causes an outlier in the sample (E_err) and affects both the demodulation processing gain and the stability of the block 330 with least common square mean. In such examples, the output signal is affected. 306 (E_sig) and the combined sample 365 (E_err) was set to zero to reduce the negative impact.

[0036] In some examples, the block processes 330 with least common square mean samples using the sampling rate of the noise suppressor 240However, it can be a decimation block 332 can be used to reduce processing requirements.

[0037] In the illustrated embodiment, the removal of the disturbance component J from the received sample is 302 Essentially independent of the code chip rate of the desired signal component, at least because the received samples are not integrated over a chip time. In the example shown, the output signal retains its value. 306 (E_sig) essentially the undistorted chip edge characteristic of the desired signal component. The essentially undistorted chip edge characteristic indicates that the output signal 306(E_sig) is essentially the same as if the signal had been transmitted (e.g., by a satellite transmitter) and is received largely in the absence of the interfering signal component. The essentially undisturbed chip edge characteristic allows the receiver 110 , to use advanced multipath avoidance techniques (e.g., hatch window, double delta code tracing, etc.).

[0038] As another example relating to the Fig. 3. Assume that the sample 302 is received at a time (t) and the sample is equal to y t is and by the equation: y t = s t + J t + n t is defined where y t the sample received at time t, s t the signal component in complex form, J t the disturbance component is represented in complex form and n tThe additive noise is in complex form. The received samples y t will be used to take M samples in the first delay line 320 delayed, which affects sample x t as defined by the equation x t = y t–M which results in the sample size x. t in the first delay line 310 buffering during the sample y t is received.

[0039] In the illustrated example, the sample x t with weightings 340 updated and by the summarizer 350 combined to sample 355 to obtain (E_LO), which is equivalent to a disturbance signal estimate J t at a time (t) (because of the larger amplitude of an interference signal, s t and n t very small, which is only J t results). The disturbance signal estimation J t will be in the block 360 to y tadded. In some examples, J t – J t = 0, therefore the disturbance J t from sample y t removed to y t' = s t + n t to result. If J is not equal to J t If, then y t' = s t + n t + δJ t , where δJ t through the block 330 The least common square mean is used to determine the weights for the next received sample y. t+1 to define the block 330 The least common square mean determines the weights by integrating a correlation between a first group of samples (e.g., for the above time (t), sample x). t–1 , sample x t–2 etc.) and a combined interference signal estimation J t and the received signal (e.g. sample y) t ).

[0040] In the example shown, the Fig. 3 sets a counter390 the delay to allow for zeroing of the sample 365 (E_err) for a block update 330 with least common square mean. In some examples, the second delay line could be used. 320 combined weights 340 no completely accurate estimate J of the input signal 302 generate. In such examples, the zeroing of the combined signal is 365 (E_err) prevents interference for a predetermined settling-in period. In some examples, the settling-in period of the interference suppressor is... 240 shorter than one modulation period of the interfering device 140 .

[0041] The diagram of Fig. 4 represents a second system 400 , which is caused by the interference suppressor 240 the Fig. 2 can be implemented. In the example shown, the system receives 400 a sample 402(E_IN) of a satellite signal and removes an interference component (e.g., an interfering signal from the source). 140 ), which has a binary phase-shift keying (BPSK) modulation. The received sample 402 is represented by the equation E_IN = S + J + N, where S equals the desired satellite signal component, J equals the disturbance (e.g., an interfering signal), and N equals noise. The sample 402 (E_IN) or its negative 404 (–E_IN) (generated from the sample 402 (E_IN) through a negation block 408 ) is used in the generation of an output signal 406 .

[0042] The in Fig. 4 illustrated exemplary systems 400 uses maximum probability criteria to decide whether the received sample 402 (E_IN) or its negative sample 404(–E_IN) into the first delay line 410 The signal is to be used to remove the interfering component J or -J from the modulation. In the illustrated example, the waveform is formed in the delay lines. 410 , 420 A sample of the sample removed from the modulation (E_IN) and the maximum probability criterion are used to determine the output signal. 406 (E_Sig) based on whether the positive sample (E_IN) or its negative 404 (–E_IN) closer to one of the delay lines 410 , 420 processed sample 455 (E_LO) is located as described below.

[0043] In the system 400 the Fig. 4. The positive sample 402 (E_IN) or the negative sample 404 at the selector 409 selected to be placed in the delay lines 410 , 420to enter, based on an output from the comparator derived from the maximum probability. 422 The comparator 422 , as described below, estimates the polarity of the received sample 402 (E_IN) based on whether the positive sample 402 (E_IN) or the negative sample 404 (–E_IN) closer to a sample (E_LO) 455 is.

[0044] The exemplary process 400 the Fig. 4 uses delay lines 410 , 420 , a block 430 using the lowest common square mean to update the weights 440 and a summing unit 450 in a similar way to the delay lines 310 , 320 , the block 330 with lowest common square mean, the weightings 340 and the summator 350 , as they relate to the Fig. 3 were described. In the example shown, the comparator 422 determine whether the sample 402 (E_IN) or its negative 404 (–E_IN) the sample 455 (E_LO) better represent. In the example shown, the receiver compares 110 the absolute value of a sample 458 (Err_m) (the difference between the negative sample ( 402 (E_IN) and the sample (E_LO)) each using the summators 456 , 460 Which of the samples 458 , 465 one closer to the sample 455 The (E_LO) value that will be used determines the polarity to select the sample. 455 (E_LO) to represent. The result of the example drives the first selector. 409 on, the binary phase-shift encryption modulation of the sample 402 to remove a continuous waveform at the delay lines 410 , 420is formed; the result also drives the second selector. 470 on, the sample 475 (Err) to result. If the sample yields Err_m 458 a sample 475 When (Err) is generated, a negative signal component (S) appears, which is a negation selector. 480 thus enabled to ensure that the positive signal component (S) in the sample 406 is maintained. Otherwise, the sample results in Err. 475 from the sample Err_p 465 , which is what the negation selector needs 480 thus makes it impossible to obtain a positive signal component (S) in the initial sample 406 to obtain.

[0045] In the system of Fig. Block 4 receives 430 with lowest common square mean a sample outcome 406 (E_Sig) from the negation selector 480 This enables the block 430to use least common square mean, δJ, to determine the weights 440 to adjust in order to generate a disturbance signal estimate J, the estimate of the disturbance component J located away from the modulation. The system 400 the Fig. 4 represents an application of the interference suppressor 240 for phase-shift encryption modulation disturbances from an exemplary interfering source (e.g., the interfering source) 140 ) by comparing whether the positive signal component J or the negative signal component –J is closer to the disturbance signal estimate J.

[0046] The diagram of Fig. 5 presents the structure of Fig. 5A to Fig. 5D representing diagram. Fig. 5A– Fig. 5D represents sections of a system 500 that is structured according to the teachings of this revelation. Thus, the present revelation refers, when it speaks of the Fig. 5 refers to the relevant Fig. 5A– Fig. 5D.

[0047] The diagram of Fig. 5 represents a system 500 , which addresses in-phase components and quadrature components, which in the exemplary receiver of the Fig. 2 can be implemented. The system 500 the Fig. Figure 5 is an example of a system for adjusting the gain of the automatic gain control to maintain a symmetrical waveform before sampling and to generate a digital sample. 504 (E_IN), which is output at a reference point A to be processed by the noise suppressor 240 the Fig. 2 to be processed, which is carried out by one or more of the systems 300 , 600 the Fig. 3 and / or Fig. 6 is implemented. The system 500 the Fig. 5 includes automatic gain control 220, an analog-to-digital converter 230 , a preload control system 510 , an amplification control system 520 , as described here. The automatic gain control 220 and the analog-to-digital converter 230 can each be controlled by the gain control 220 and the analog-to-digital converter 230 the Fig. 2 will be implemented. The gain control system 520 adjusts the gain of the gain control 220 , so that the amplitude of the received signals is essentially limited by the sensitivity of the analog-to-digital converter 230 is adjusted. The preload control system 510 (engl.: bias control system) maintains a DC voltage component at the output of the analog-to-digital converter. 230 to zero.

[0048] The gain control system 520 and the preload control system 510can ensure that clipping-free and DC-free samples are sent to a noise suppressor via a reference point A 240 the Fig. 2 will be provided, which is provided by the systems 300 , 600 the Fig. 3 and / or Fig. 6 is implemented.

[0049] In the system of Fig. 5 sets an automatic gain control 220 an amplification of the receiver 110 so fixed that the amplitude of a received signal 502 with the maximum range (e.g. 8 bits, by [7:0] in the analog-to-digital converters 230 (shown) of an analog-to-digital converter 230 fits together without cutting off the received signal 502 using the gain control system 520 In the example shown, the Fig. 5 detects the gain control system 520 the sudden change in strength of the received signal 502In some examples, changes in the strength of the received signal are observed. 502 due to the presence and / or absence of an interference signal (e.g., the interference signal J of the Fig. 3 and / or Fig. 4, a disturbance signal etc.) is required.

[0050] In the Fig. 5 receives the automatic gain control 220 an analog input signal 502 , which is represented by I_IN (in-phase signal component) and Q_IN (quadrature signal component). The automatic gain control 220 transmits both components of the signal 502 , so that they can be combined with an appropriate preload, which is determined by the preload checks 512 , 514 in the preload control system 510 The signal, freed from bias, is processed by the analog-to-digital converter. 230 quantized to convert the analog signal 502 into a digital signal 504(E_IN) to convert. In the example shown, the output of the analog-to-digital converter is 230 equal to the following equation: AD out = min(max(–AD max , round(AD in )), AD max ).

[0051] The interference suppressor 240 The example shown uses the gain control system. 520 and the preload control system 510 , in order to operate in a continuous mode. Therefore, if unreliable operation of either the preload control system occurs, 510 or the gain control system 520 When detected, the interference suppressor is activated. 240 The example shown is reset via a reference point B. In some examples, the noise suppressor can be 240 reset by using a delay line and / or weights (e.g., the delay lines). 320 , 420 and / or the weightings320 , 420 the Fig. 3 and / or Fig. 4) be set to zero.

[0052] If in the Fig. In the example shown in point 5, if a disturbing signal strength increases or clipping occurs, the gain control system detects this. 520 that a metric 528 the automatic gain control, which corresponds to quantized samples with a maximum amplitude, a threshold 522 (AGC_MAX) is exceeded. In such examples, the gain control system reduces 520 the amplification of the automatic gain control 220 and the one associated with the system 500 the Fig. 5 interference suppressors used 240 are being reset because the current estimate of the interference signal may no longer be accurate.

[0053] In some examples, the gain control system detects 520 , if the metric 528automatic gain control below a minimum threshold 524 (AGC_MIN). In such examples, the automatic gain control system increases the value. 520 the amplification of the automatic gain control 220 and the processes (e.g. the systems) 300 , 600 the Fig. 3 or Fig. 6) of the interference suppressor 240 , which are associated with the process 500 the Fig. 5 will be used, will be restarted, as the current estimate of the interference signal is no longer accurate.

[0054] In some examples, it is claimed that the automatic gain control 220 operates continuously when the metric 528 the gain control between the minimum threshold 524 and the maximum threshold 522 is. Such examples illustrate the metric 528gain control by a comparator network 519 with a threshold 523 compared. The result of this comparison drives the gain control unit. 560 , the amplification of the automatic gain control 220 to adapt.

[0055] In the illustrated example of the preload control system 510 the Fig. The bias counter generates 5. 518 the preload metric to (1) adjust the preload using the preload adjusters 512 , 514 to adjust and (2) the operating mode of the bias control system 510 by comparing the prestress metric with a prestress threshold 516 to monitor. Resetting the interference suppressor. 240 This happens when the bias metric of the bias meter 518 the threshold 516 exceeds.

[0056] The phase-in-phase components and quadrature components of the analog-to-digital converter 230 form a sample 504 (E_IN) the Fig. 5, which are connected to the interference suppressor via a reference point A of the diagram 240 be supplied.

[0057] The diagram of Fig. Figure 6 presents a diagram illustrating the structure of Fig. 6A– Fig. 6B depicts the Fig. 6A– Fig. 6B form sections of a system 600 from which, according to the teachings of this revelation, the revelation refers to the corresponding Fig. 6A– Fig. 6B, if they click on the Fig. 6 refers.

[0058] The diagram of Fig. 6 is representative of a system 600 , an implementation of the system 300 the Fig. 3, which are the interference suppressors of the Fig. 2 can implement. The system 600can be connected to the system via reference points A and B 500 the Fig. 5. They are communicatively coupled. The diagram of the Fig. Figure 6 shows an example system 600 to receive a sample 604 (E_IN), which is an implementation of the sample 504 (E_IN) the Fig. 5 can be a signal that contains signal (S), interference or superposition (J), and noise (N) components. The system 600 generates a disturbance signal estimate J, removes some or all of the disturbance components J, and outputs a signal component 606 (E_sig) out.

[0059] In an exemplary operation of the system 600 the Fig. 6 will be a sample 604 , E_IN = S + J + N, from the analog-to-digital converter 230 the Fig. 5 received via a reference point A. The sample 604(E_IN) has both an (in-phase) I-component and a Q-component (quadrature). The I- and Q-components of the sample 604 proceed through the two sets of delay lines 610 , 612 and 620 , 622 further, so that the I-component passes through the delay lines 610 , 620 and the Q component through the delay lines 612 , 622 running. The sample 604 will be in the first delay lines 610 , 612 buffered for a threshold number of samples before they enter the second delay line 620 , 622 to be moved. The first delay lines 610 , 612 ensure that the samples are in the second delay lines 620 , 622 are from a different chip than the sample 604In some examples, the threshold number of samples is denoted as M, where M = F S / F CHIP and F S equal to the sampling frequency and F CHIP selected as the lowest chip rate or time-division multiplexed chip rate, e.g. 0.511 MHz for navigation applications.

[0060] The first delay lines 610 , 612 enable the process 600Maintaining the correlation for an interfering signal, e.g., a noise signal, as described herein, is challenging because the noise signal covers multiple chips and will therefore be correlated between the chips, even with a delay between samples, which means the samples are parts of different chips. However, the number of samples M in the delay is greater than one chip, which decorrelates the desired signal component, since sections of the desired signal components combined with different chips are not correlated. Thus, thanks to the first delay lines... 610 , 612 The only components correlated between neighboring chips are the interference components.

[0061] In the example shown, the sample moves 604 into the respective second delay lines 620 , 622 , after the sample 604 in the first delay lines 610 ,612 waits. A block 330 with smallest mean squares 630 with an exemplary subsystem 642 To generate a correction for a tap, a correction weighting vector is created. 640 for L taps. The accumulated correction vector results in a weighting estimate. For the subsystem 642 complete blocks 680 , 682 a complex multiplication of Sgn (E_err)·(I[k] + jQ[k]), where (E_err) is an error signal 665 , I[k] an in-phase element from the delay line 620 and Q[k] a quadrature component from the delay line 622 is, which is a single weighting correction 684 generated. The integral of the signal 684 through the k-th adder in the network 684 represents the current k-th weighting estimate.

[0062] In some examples, the delay lines 610, 620 , 612 , 622 and correction weighting factors 640 reset as soon as the transition operating mode is reset by the exemplary systems 510 , 520 the Fig. 5 are observed as described herein.

[0063] The weightings in the network 648 They become complex with the samples in the second delay lines. 620 , 622 multiplied to calculate using the summing function 650 a disturbance signal assessment 655 to obtain (E_LO).

[0064] To determine the disturbance component J of the received sample 604 To identify and remove the received sample 604 with a disturbance signal estimation 655 (E_LO) (i.e., the perturbation signal estimation J) combined to create a sample 665 to obtain. The combined sample 665can be defined by E_err = S + N + δJ, where δJ equals J – J. In the example shown, the comparator 670 , the selectors 672 , 694 and logic that sets to zero from a gate 692 (which are similar to those in the system) 300 the Fig. 3 described counterparts 370 , 372 , 394 , and 392 (operating) used to ensure the operational stability of the interference suppressor 240 to maintain.

[0065] In the example shown, the distance of the disturbance component J from the sample received is 604 essentially independent of the code chip rate of the desired signal component. In the example shown, the output signal retains 606 (E_sig) essentially the undistorted chip edge characteristic of the desired signal component. The essentially undistorted chip edge characteristic indicates that the output signal606 (E_sig) is essentially the same as if the signal had been transmitted (e.g., from a satellite transmitter) and is received largely in the absence of the interfering signal component J. The essentially undisturbed chip edge characteristic allows the receiver 110 , to use advanced multipath avoidance techniques (e.g., hatch window, double delta code tracing, etc.).

[0066] In the example shown, the Fig. 6 sets a counter 690 , similar to the counter 390 according to the example Fig. 3, a delay to zero out the sample (E_Err) for the block 630 the smallest mean squares (using the gate 692 , of the second selector 694 and a low-sampler 698 ) (using the first selector) 672 ) to enable).

[0067] Example machine-readable instructions 700, which are used to implement the noise suppressor 240 the Fig. 2 can be executed, are through the in Fig. The flowchart shown in section 7 illustrates this. The instructions begin at block 7. 710 and at a block 720 The interference suppressor 240 determine whether a digital sample (e.g., the samples) 302 , 402 , 504 , 604 ) including a desired signal component (e.g., the signal S, the signal S + noise N, etc., as with respect to the Fig. 3 to Fig. 6) and an interfering signal component (e.g., the interfering signal J, an interfering signal, etc.) is received. In some examples, the digital signal sample is received from a satellite of a spreadband navigation system. If in the block 720 If no sample is received, the control moves to the block. 760 and the instructions of Fig. 7 ends.

[0068] If in the block 720 When a signal is received, the control unit moves to the block. 730 . In the block 730 The interference suppressor generates 240 A noise signal estimation of the interfering signal component based on a group of received samples. In some examples, the received samples were pre-sampled. 720 received. In some examples, the interference signal estimation is an estimation of the phase and amplitude of the interfering signal. In the example shown, the Fig. 7 uses the interference suppressor 240 an exemplary first delay line (e.g. the delay lines) 310 , 410 , 610 , 612 ) as a buffer. The first delay line stores M samples, where M = F S / F CHIP and F S is equal to the sampling frequency and F CHIPThe chip rate can be selected as the lowest chip rate or a time-division multiplexed chip rate, e.g., 0.511 MHz for satellite navigation applications. The first delay line ensures that there is no correlation between any desired signal components in samples from a second delay line (e.g., the delay lines). 320 , 420 , 620 and 622 ) and the desired signal component of the sample of the block 720This would occur because M is longer than one chip. The interference signal spans multiple chips and will therefore be correlated between chips, even with a delay between samples that makes the samples part of different chips. However, the number of samples M in the delay line is longer than one chip, which decorrelates the desired signal component, since sections of the desired signal component combined with different chips are uncorrelated. Thus, the only correlation between the samples would be... 720 and each of the sample groups the interfering signal component.

[0069] In the block 730 The interference suppressor moves 240 a sample into a second delay line (e.g. the second delay lines) 320 , 420 , 620 , 622), which has a length L, where L is the number of samples in the delay line. As mentioned above, the L samples in the second delay line are from a different chip than those in the block. 720 received digital sample. In some examples, the number of samples in the group of samples is equivalent to L. Furthermore, the noise suppressor uses 240 in the block 730 a least mean squares analysis (e.g. the blocks) 330 , 430 , 630 the Fig. 3, Fig. 4, Fig. 6) to establish update weights to be applied to the group of samples stored in the second delay line. Least mean squares analysis is based on one or more previously issued, estimated, and / or received samples that are complexly correlated with an error signal.

[0070] Furthermore, the interference suppressor modulates within the block.730 the weighted samples from the second delay line via a summing unit (e.g. the summing units) 350 , 450 , 650 , etc.). Modulating the group of samples yields the noise signal estimate (e.g., the noise signal estimate J). In some examples, modulating the group of weighted samples only yields the noise signal estimate, at least because the amplitude of the noise signal components is much larger than the signal components or noise components of the samples from the group of samples.

[0071] In the block 740 the Fig. 7 combines the interference suppressor 240 the interference signal estimation of the block 730 with the sample of the block 720in order to at least partially remove the interfering signal component from the sample. In the example shown, the combination of the interfering signal estimation and the sample results at least partially in the removal of the interfering signal component from the sample, since the interfering signal estimation in the block 730 is generated based on previously received samples. Furthermore, if the previously received samples are modulated, the only correlation between the samples is some interfering signal component, for example, a noise signal. The noise signal estimate is accordingly generated to account for the noise signal component of the block's signal sample. 720 to counteract this. In the example shown, the removal of the interfering signal component can be achieved without considering the receiver's chip type. 110 and / or the interference suppressor 240 take place.

[0072] After the block 740 the Fig. 7 the control goes to the block 750 and outputs the combination of the disturbance signal estimation and the sample. In the examples disclosed and shown here, the output signal of the block is 750 from the recipient 110 processed. After the block 750 The control goes to the block 720 back to monitor the receipt of the next sample.

[0073] The Fig. Figure 8 is a block diagram of an example processor platform 800 , which is capable of implementing the systems, processes and / or instructions of the Fig. 3 to Fig. 7 to execute in order to reach the recipient of the Fig. 1 and / or Fig. 2 to implement. The processor platform 800 This could be, for example, a server, a personal computer, a mobile phone (e.g., a GSM phone), a personal digital assistant (PDA), an internet application, or any other type of computing device.

[0074] The processor platform 800 The present example includes a processor 812 For example, the processor can 812 by one or more microprocessors or microcontrollers of any desired family or from any manufacturer.

[0075] The processor 812 includes local storage 813 (e.g. a cache) and is accessible via a bus 818 in communication with a main memory with a volatile memory 814 and a non-volatile memory 816 The volatile memory 814 It can be implemented using SDRAM (Synchronous Dynamic Random Access Memory), DRAM (Dynamic Random Access Memory), RAMBUS (Dynamic Random Access Memory), and / or any other type of freely accessible storage device. The non-volatile memory 816can be implemented using flash memory and / or any other desired type of storage device.

[0076] The processor platform 800 It also includes an interface circuit. 820 The interface circuit 820 can be implemented through any type of interface standard, such as an Ethernet interface, a universal serial bus (USB), and / or a PCI Express interface.

[0077] One or more input devices 822 are connected to the interface circuit 820 connected. The input device(s) allow a user to send data and instructions to the processor. 812 to input. The input device(s) can be implemented, for example, by a keyboard, a mouse, a touch-sensitive screen, a track pad, a track ball, an isodot and / or a speech recognition system.

[0078] One or more output devices 824 are also connected to the interface circuit 820 connected. The output devices 824 These can be implemented, for example, by display devices (e.g., a liquid crystal display, a cathode ray tube, a printer, and / or a loudspeaker). The interface circuit 820 It therefore typically includes a graphics driver card.

[0079] The interface circuit 820 It also includes a communication device, such as a modem or network interface card, to facilitate the exchange of data with external computers over a network (e.g., an Ethernet connection, a digital subscript line (DSL), a telephone line, coaxial cable, a GSM telephone system, etc.).

[0080] The processor platform 800 also includes one or more mass storage devices 828For storing software and data. Examples of such mass storage devices. 828 This includes floppy disk drives, hard drives, CD drives and DVD drives.

[0081] The coded instructions 832 , which the systems, processes and / or coded instructions 300 , 400 , 500 , 600 , 700 the Fig. 3 to Fig. 7 implement, can be implemented in the mass storage device 828 , in volatile memory 814 , in non-volatile memory 816 and / or be stored on a removable storage medium such as a CD or DVD.

[0082] From the foregoing, it will be estimated that the above-disclosed methods, apparatus, and manufacturing articles provide a method and apparatus for improving signal reception from a received sample by removing an interfering signal from the sample. This is achieved by estimating the phase and amplitude of the interfering signal at the time of each received sample using more than one delay line, a weighting system, and least mean squares analysis. The remaining sample retains the original GNSS chip edge characteristics. The disclosed methods, apparatus, and manufacturing articles provide a method and apparatus for improving signal reception independent of the GNSS code chip rate, thus enabling the receiver to receive any of the upgraded GNSS signals.

[0083] Although certain exemplary processes, apparatus, and articles have been described herein, the scope of protection of this patent is not limited to them. On the contrary, this patent covers all processes, apparatus, and articles that fall within the scope of protection of the claims of this patent.

Claims

[1] Method for improving the signal reception of a satellite navigation receiver, comprising the following steps: Receiving a composite satellite signal that includes a desired signal component and an interfering signal component, Converting the received composite satellite signal into a digital received composite signal, Receiving a first group of samples of the digitally received composite signal, Generating a disturbance signal estimate of the disturbing signal component based on the first group of samples, and Combining the interference signal estimation and a second sample belonging to a second group of samples to be eliminated, in order to remove all or part of the interfering signal component from the composite satellite signal, wherein the first group of samples was received before the sample belonging to the second group of samples, wherein the removal is substantially independent of a spreading code rate of the desired signal component and substantially preserves the undisturbed spreading edge characteristic of the desired signal component. [2] Method according to claim 1, wherein the generation of the disturbance signal estimation comprises generating a disturbance estimation of the amplitude and phase of the disturbing signal components and a weighted combination of the first group of samples. [3] Method according to claim 2, further comprising updating weights used in the weighting by a least mean squares process. [4] Method according to claim 3, wherein the least mean squares process updates the weights by integrating a correlation between the first group of samples and the combined disturbance signal estimation and the sample belonging to the second group of samples. [5] Method according to claim 1, wherein the first group of samples relates to a first communication chip and the second group of samples relates to a second communication chip which differs from the first communication chip. [6] Method according to claim 5, wherein the second communication chip is spaced at least one communication chip apart from the first communication chip. [7] Method according to claim 1, wherein the first group of samples and the second group of samples are connected to a spread spectrum navigation system. [8] Arrangement for improving the signal reception of a satellite navigation receiver, comprising: a receiver for receiving a composite satellite signal comprising a desired signal component and an interfering signal component, a converter for converting the received composite satellite signal into a digital received composite signal, a noise suppressor for receiving a first group of samples of the digitally received composite signal, for generating a noise signal estimate of the interfering signal component based on the first group of samples, and for combining the noise signal estimate with a second sample belonging to a second group of samples to be eliminated in order to remove all or part of the interfering signal component from the composite satellite signal, wherein the first group of samples was received before the sample belonging to the second group of samples, wherein the removal is substantially independent of a spreading code rate of the desired signal component and substantially preserves the undisturbed spreading edge characteristic of the desired signal component. [9] Arrangement according to claim 8, wherein the generation of the disturbance signal estimation comprises generating a disturbance estimation of the amplitude and phase of the disturbing signal components and a weighted combination of the first group of samples. [10] Arrangement according to claim 9, wherein the interference suppressor is further configured to update the weightings used according to a least mean squares process. [11] Arrangement according to claim 10, wherein the least mean squares process updates the weights by integrating a correlation between the first group of samples and the combined disturbance signal estimation and the sample belonging to the second group of samples. [12] Arrangement according to claim 8, wherein the first group of samples relates to a first communication chip and the second group of samples relates to a second communication chip which differs from the first communication chip. [13] Arrangement according to claim 12, wherein the second communication chip is spaced at least one communication chip apart from the first communication chip. [14] Arrangement according to claim 13, wherein the first group of samples and the second group of samples are connected to a spread spectrum navigation system. [15] Touchable machine-readable medium containing machine-readable instructions which, when executed, cause a machine to do the following: to receive a composite satellite signal that includes a desired signal component and an interfering signal component, to convert the received composite satellite signal into a digital received composite signal, to receive an initial group of samples of the digitally received composite signal, to generate a disturbance signal estimate of the disturbing signal component based on the first group of samples, to combine the interference signal estimation and a second sample belonging to a second group of samples to be eliminated in order to remove all or part of the interfering signal component from the composite satellite signal, wherein the first group of samples was received before the sample belonging to the second group of samples, wherein the removal is substantially independent of a spreading code rate of the desired signal component and substantially preserves the undisturbed spreading edge characteristic of the desired signal component. [16] Medium according to claim 15, wherein the generation of the disturbance signal estimation comprises generating a disturbance estimation of the amplitude and phase of the disturbing signal components and a weighted combination of the first group of samples. [17] Medium according to claim 16, further comprising updating weightings used in the weighting by a least mean squares process. [18] Medium according to claim 17, wherein the least mean squares process updates the weights by integrating a correlation between the first group of samples and the combined disturbance signal estimation and the sample belonging to the second group of samples. [19] Medium according to claim 15, wherein the first group of samples relates to a first communication chip and the second group of samples relates to a second communication chip which differs from the first communication chip. [20] Medium according to claim 19, wherein the second communication chip is spaced at least one communication chip apart from the first communication chip. [21] Medium according to claim 15, wherein the first group of samples and the second group of samples are connected to a spread spectrum navigation system.