Methods and apparatus for detecting potential faults in positioning devices

Abstract

This application relates to a method and apparatus for detecting potential faults in a positioning device. The apparatus includes at least one memory for storing instructions; and at least one controller configured to execute the instructions to perform operations including: obtaining information about received signals received by the positioning device, the information including at least one of control parameters and deviation estimates based on the received signals; determining whether a potential fault has been detected based on the information and a detection threshold; and generating an indication that a potential fault has been detected in response to determining that a potential fault has been detected.

Description

Technical Field

[0001] This disclosure relates to fault detection in positioning devices, and more specifically to methods and apparatus for detecting potential faults in positioning devices. Background Technology

[0002] Monitoring the receiver and the condition of the received signal in a positioning device enables the provision of accurate and reliable location information. The optimal functioning of external components and circuitry is expected to support the operation of the receiver within the positioning device. However, failures in external circuitry or components may go undetected and are instead detected as signal loss in the receiver's received signal. For example, a fault in the matching element of a surface acoustic wave (SAW) filter due to vibration may be detected as distortion in the receiver's received signal. The receiver may still be able to receive new signals and provide location information through the SAW filter. However, a fault in the SAW filter's radio frequency (RF) path can cause poor group delay characteristics in the newly received signal, which can lead to significant variations in measurement results and result in location errors. Summary of the Invention

[0003] Embodiments of this application provide improved methods and apparatus for detecting potential faults in positioning devices.

[0004] These embodiments include an apparatus for detecting potential faults in a positioning device. The apparatus includes: at least one memory for storing instructions; and at least one controller configured to execute the instructions to perform operations including: obtaining information relating to received signals received by the positioning device, the information including at least one of control parameters and deviation estimates based on the received signals; determining whether a potential fault has been detected based on the information and a detection threshold; and generating an indication that a potential fault has been detected in response to determining that a potential fault has been detected.

[0005] These embodiments also include a method for detecting potential faults in a positioning device. The method includes the steps of: obtaining information relating to received signals received by the positioning device, the information including at least one of control parameters and deviation estimates based on the received signals in the positioning device; determining, based on the information and a detection threshold, whether a potential fault has been detected; and generating an indication that a potential fault has been detected in response to determining that a potential fault has been detected.

[0006] These embodiments also include a non-transitory computer-readable medium for storing instructions that, when executed, cause the controller to perform operations for detecting a potential fault in the positioning device. The operations include: obtaining information relating to received signals received by the positioning device, the information including at least one of control parameters and deviation estimates based on the received signals; determining, based on the information and a detection threshold, whether a potential fault has been detected; and generating an indication that a potential fault has been detected in response to determining that a potential fault has been detected. Attached Figure Description

[0007] Figure 1 This is a block diagram of an exemplary fault detector and an exemplary receiver for a positioning device consistent with embodiments of this disclosure.

[0008] Figure 2 This is a flowchart of an exemplary method for detecting potential faults in a positioning device, consistent with embodiments of this disclosure.

[0009] Figure 3 This is a block diagram of an exemplary circuit in a receiver of a positioning device consistent with embodiments of the present disclosure, the exemplary circuit including an exemplary amplifier, a filter, an analog-to-digital converter, and an automatic gain controller.

[0010] Figure 4 This is a block diagram of an exemplary positioning device consistent with embodiments of this disclosure.

[0011] Figure 5 This is a block diagram of an exemplary antenna subsystem of a positioning device consistent with embodiments of the present disclosure. Detailed Implementation

[0012] Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings, in which, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments set forth in the following description of exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with aspects of the invention as enumerated in the appended claims.

[0013] Figure 1 This is a block diagram of an exemplary fault detector 140 and an exemplary receiver 120 of a positioning device 160 consistent with embodiments of this disclosure. Figure 1 As shown, the positioning device 160 includes a receiver 120 and a fault detector 140. The receiver 120 includes an automatic gain controller (AGC) 122, a digital processing circuit 124, a tracking engine 126, and a navigation engine 128. The fault detector 140 includes a controller 142 and a memory 144. It may include... Figure 1 One or more of these components are used to detect potential faults in the positioning device 160. These components can be configured to transmit data between or among each other and to send or receive instructions.

[0014] In receiver 120, AGC 122, digital processing circuit 124, tracking engine 126 and navigation engine 128 are connected in sequence to receive signals via input terminal 101, determine position and navigation information based on the received signals, and output the navigation information to, for example, a user, a navigation user interface, a navigation device or a server via output terminal 103.

[0015] AGC 122 is configured to control the received signal strength at the input of digital processing circuit 124 to meet the signal-to-noise ratio (SNR) required for proper analog-to-digital conversion and digital processing. For example, if the received signal strength at input 101 is weak, AGC 122 is configured to boost the received signal gain to minimize noise and achieve an acceptable SNR. If the received signal strength is strong, AGC 122 is configured to attenuate the received signal gain to avoid signal clipping and nonlinear degradation, which could worsen the SNR of the received signal.

[0016] Digital processing circuitry 124 is configured to receive and process received digital signals. In some embodiments, digital processing circuitry 124 includes a processor configured to execute instructions stored in a memory to receive and process the received digital signals. Digital processing circuitry 124 is configured to filter, demodulate, and decode the received digital signals to obtain information transmitted from one or more satellites, and to send the information to tracking engine 126.

[0017] Tracking engine 126 is configured to track and detect the current position of positioning device 160. In some embodiments, tracking engine 126 includes a processor configured to execute instructions stored in memory to track and detect the current position of positioning device 160. Tracking engine 126 is configured to receive messages from satellites and determine the current position of positioning device 160 based on current and / or previous messages from satellites.

[0018] Navigation engine 128 is configured to provide navigation information based on positioning information from tracking engine 126. In some embodiments, navigation engine 128 includes a processor configured to execute instructions stored in memory to provide navigation information based on the positioning information. Navigation engine 128 is configured to obtain the current position from tracking engine 126 and determine navigation information based on the current position, previous position, and / or map information. Navigation engine 128 is configured to output the navigation information via output terminal 103.

[0019] In some implementations, the digital processing circuitry 124, the tracking engine 126, and / or the navigation engine 128 may be configured to perform reference... Figure 1 The same circuitry, processor, and memory are used for the described operations. For example, the processor and memory may be configured to perform the operations of the described digital processing circuitry 124, tracking engine 126, and navigation engine 128. As another example, the digital processing circuitry 124 includes digital circuitry for digital signal processing, and the processor and memory are configured to perform the operations of the described tracking engine 126 and navigation engine 128.

[0020] In fault detector 140, controller 142 is coupled to memory 144. Controller 142 includes any suitable type of general-purpose or special-purpose microprocessor, digital signal processor, or microcontroller. Controller 142 may represent one or more processors and / or controllers in fault detector 140.

[0021] Memory 144 may include any suitable type of mass storage device provided to store any type of information that may be required to enable the controller 142 to operate. Memory 144 may be volatile or non-volatile, magnetic, semiconductor, magnetic tape, optical, removable, non-removable, or other types of storage devices or tangible (i.e., non-transitory) computer-readable media, including but not limited to read-only memory (ROM), flash memory, dynamic random access memory (RAM), and static RAM. Memory 142 may be configured to store one or more programs for execution by the controller 142 for detecting potential faults in the positioning device 160, as disclosed herein.

[0022] The memory 144 can also be configured to store information and data used by the controller 142. For example, the memory 144 can be configured to store gain, bias, and threshold values ​​used to detect potential faults in the positioning device 160.

[0023] In some embodiments, the controller 142 and memory 144 of the fault detector 140 may be the same circuitry, processor, and / or memory as the receiver 120, which are configured to perform operations for detecting potential faults in the positioning device 160, as disclosed herein.

[0024] like Figure 1 As shown, fault detector 140 is configured to receive programmable gain amplifier (PGA) gain from AGC 122 of receiver 120 via connection 121. Controller 142 is configured to execute instructions stored in memory 144 to detect potential faults in positioning device 160 based on the PGA gain, as disclosed herein. Alternatively, fault detector 140 is configured to receive inter-channel deviation, inter-system deviation, and / or inter-band deviation from navigation engine 128 of receiver 120 via connection 123. Controller 142 is configured to execute instructions stored in memory 144 to detect potential faults in positioning device 160 based on inter-channel deviation, inter-system deviation, and / or inter-band deviation, as disclosed herein.

[0025] Figure 2 This is a flowchart of an exemplary method 200 for detecting a potential fault in a positioning device (e.g., positioning device 160), consistent with embodiments of this disclosure. Method 200 may be implemented by a fault detector 140 disclosed and executored herein. For example, a controller 142 is configured to execute instructions stored in a memory 144 to perform the operation of method 200. Method 200 includes: obtaining information about received signals received by the positioning device (step 220); determining whether a potential fault is detected based on the information and a detection threshold (step 240); and generating an indication that a potential fault has been detected in response to determining that a potential fault has been detected (step 260).

[0026] Step 220 includes obtaining information about received signals received by the positioning device. This information includes at least one of control parameters and deviation estimates based on the received signals. For example, such as... Figure 1 As shown, the fault detector 140 is configured to receive information about the PGA gain from the AGC 122 of the receiver 120 via connection 121. The PGA gain is a gain control parameter determined by the AGC 122 based on the signal strength of the received signal received by the positioning device 160. The AGC 122 is configured to determine the PGA gain and send it to the PGA in the positioning device 160 to control the gain of the PGA for the received signal.

[0027] As another example, fault detector 140 is configured to receive information about inter-channel offset, inter-system offset, and / or inter-band offset from navigation engine 128 of receiver 120 via connection 123. Inter-channel offset, inter-system offset, and / or inter-band offset are estimates of the offsets estimated by receiver 120 based on received signals received by positioning device 160.

[0028] Alternatively, fault detector 140 may be configured to receive both information about PGA gain and information about inter-channel offset, inter-system offset, and / or inter-band offset for detecting potential faults in positioning device 160, as described below.

[0029] Step 240 includes determining whether a potential fault has been detected based on the information and a detection threshold. For example, fault detector 140 is configured to determine whether a potential fault has been detected based on information about the PGA gain and a gain threshold through the following steps: Fault detector 140 is configured to compare the PGA gain with a gain threshold. Fault detector 140 is configured to determine that a potential fault has been detected in positioning device 160 in response to a comparison result indicating that the PGA gain is greater than the gain threshold.

[0030] Alternatively, fault detector 140 may be configured to determine whether a potential fault has been detected by the following steps based on information regarding inter-channel offset, inter-system offset and / or inter-band offset, upper offset threshold and lower offset threshold. Fault detector 140 is configured to compare one of the offsets with at least one of the corresponding upper offset threshold or lower offset threshold. Fault detector 140 is configured to determine that a potential fault has been detected in positioning device 160 in response to a comparison result that one of the offsets is greater than the corresponding upper offset threshold or less than the corresponding lower offset threshold.

[0031] In some implementations, fault detector 140 may be configured to compare a plurality of deviations with corresponding upper deviation thresholds or lower deviation thresholds. Fault detector 140 is configured to determine that a potential fault has been detected in positioning device 160 in response to a comparison result that one or more of the plurality of deviations are greater than the corresponding upper deviation threshold or less than the corresponding lower deviation threshold.

[0032] Furthermore, in some embodiments, the fault detector 140 may be configured to determine whether a potential fault has been detected based on both information about the PGA gain and information about inter-channel offset, inter-system offset and / or inter-band offset, gain threshold, upper offset threshold and lower offset threshold, as described in the embodiments herein.

[0033] Step 260 includes: generating an indication that a potential fault has been detected in response to determining that a potential fault has been detected. For example, fault detector 140 is configured to generate an indication that a potential fault has been detected in positioning device 160 when fault detector 140 determines that a potential fault has been detected. This indication may be an alarm for a potential fault in positioning device 160. The alarm may be used to indicate the reliability of the current positioning result of positioning device 160. Alternatively, the alarm may be used to determine whether navigation information should be updated based on the current positioning result.

[0034] Figure 3 This is a block diagram of an exemplary circuit 300 in a receiver of a positioning device, consistent with embodiments of this disclosure. The exemplary circuit 300 includes: an exemplary amplifier, a filter, an analog-to-digital converter, and an automatic gain controller. Figure 3 As shown, circuit 300 includes a low-noise amplifier (LNA) 320, a low-pass filter (LPF) 340, a PGA 360, an analog-to-digital converter (ADC) 380, and an automatic gain controller (AGC) 350. The LNA 320, LPF 340, PGA 360, ADC 380, and AGC 350 are connected in sequence to process the received signal from input 301 and output the received digital signal at output 303. AGC 350 is also connected to PGA 360 via connection 355.

[0035] LNA 320, LPF 340, and PGA 360 are configured to amplify and filter the received signal from input 301. ADC 380 is configured to convert the amplified and filtered received signal into a received digital signal. AGC 350 is configured to determine an appropriate gain for subsequent received signals based on the currently received digital signal and send that appropriate gain as a gain control parameter to PGA 360 via connection 355. PGA 360 is configured to amplify or attenuate subsequent received signals based on the gain control parameter from AGC 350 to obtain an appropriate SNR.

[0036] Figure 1 AGC 122 can be used as Figure 3 The AGC 350 in the positioning device 160 is used for operation. The LNA 320, LPF 340, PGA 360 and ADC380 can be similar components connected to the AGC 122 of the receiver 120 in the positioning device 160. Therefore, the circuit 300 is described below as being connected to receive the input 101 of the receiver 120, wherein the AGC 350 operates as the AGC 122.

[0037] The AGC 350 is configured to adjust the gain of the PGA 360 to an appropriate gain value based on the signal strength of the initially received signal when the positioning device 160, including circuitry 300, begins receiving signals for positioning. The received signal may have varying signal strength due to interference and / or noise. However, the gain of the PGA 360 may rise and fall as all components of the positioning device 160 function fully, but will remain within a gain threshold.

[0038] When a fault exists in a component of the positioning device 160, the fault may cause an abnormal degradation in the signal strength of the received signal. The AGC 350 is configured to increase the gain of the PGA 360 when the signal strength of the received signal degrades in order to maintain a stable signal strength, which may result in a significant increase in the gain of the PGA 360. Due to the fault in a component of the positioning device 160, the increased gain of the PGA 360 may exceed a gain threshold. Therefore, method 200 can be implemented by the fault detector 140 to detect a potential fault in a component of the positioning device 160, as described below.

[0039] The information about the received signal at step 220 includes information about gain control parameters. These gain control parameters are, for example, the current gain G of the PGA 360. c The AGC 350 has this current gain G c Settings are configured to maintain an appropriate signal strength for the received signal. After the positioning device 160 is initialized and begins receiving signals for positioning, the PGA 360 has a nominal gain G. N The nominal gain G of the PGA 360 N This refers to the gain that enables receiver 120 to receive signals with appropriate signal strength for positioning. The nominal gain G is achieved when all components of the positioning device 160 are functioning optimally. N It can be the average gain that supports the normal operation of the positioning device 160 and provides accurate location.

[0040] The detection threshold in step 240 includes the following gain threshold: This gain threshold is equal to the nominal gain G. N Adding the gain increment dG, i.e., the gain threshold = G N +dG. For example, the incremental value of gain dG can be 3dB or 5dB, which is the margin that allows the gain of the PGA360 to vary due to interference and / or noise.

[0041] Determining whether a potential fault is detected at step 240 includes determining:

[0042]

[0043] Specifically, determining whether a potential fault is detected at step 240 includes comparing a gain control parameter with a gain threshold. Step 240 further includes determining that a potential fault is detected in response to a comparison result that the gain control parameter is greater than the gain threshold. Step 240 further includes determining that no potential fault is detected in response to a comparison result that the gain control parameter is less than or equal to the gain threshold.

[0044] In other words, the fault detector 140 is configured to: if the current gain G of the PGA 360... c Less than or equal to the gain threshold, i.e., G c ≤G N If +dG is detected, it is determined that no potential fault has been detected. Fault detector 140 is configured to: if the current gain G of PGA 360 is +dG, then it is determined that no potential fault has been detected. c Greater than the gain threshold, i.e., G c >G N +dG indicates that a potential fault has been detected.

[0045] In some implementations, the gain control parameter obtained at step 220 includes the current gain of the PGA in the receiver of the positioning device. The gain threshold in step 240 includes the nominal gain of the PGA plus an increment value of the gain. For example, the gain control parameter obtained by fault detector 140 is the current gain G of the PGA 360 in receiver 120 of positioning device 160. c The fault detector 140 will measure the current gain G of the PGA 360. c Compared to a gain threshold, which includes the nominal gain G of the PGA 360. N Add the incremental value of gain, dG.

[0046] In some implementations, the nominal gain in method 200 includes at least one of the following: a predetermined gain value stored in at least one memory; an initial gain value obtained from the initialization of the receiver; or a low-pass filtered gain value.

[0047] For example, the controller 142 of the fault detector 140 is configured to read a predetermined gain value stored in the memory 144 as the nominal gain G. N The predetermined gain value can be input by the user and stored in memory 144. Alternatively, the predetermined gain value can be the average gain of PGA 360 when receiver 120 receives a signal for positioning in a previous time.

[0048] As another example, when receiver 120 is configured to execute an initialization procedure, controller 142 of fault detector 140 can be configured to obtain the initial gain value of PGA 360 as the nominal gain G. NWhen receiver 120 executes the initialization procedure, AGC 350 is configured to control the gain of PGA 360 to an appropriate value that allows receiver 120 to receive signals with suitable signal strength for positioning. Controller 142 is configured to use the initial gain value as the nominal gain G. N The value is stored in memory 144. Alternatively, controller 142 can be configured to use the initial gain value as the nominal gain G. N It is stored in a one-time programmable memory.

[0049] Alternatively, the controller 142 of the fault detector 140 can be configured to obtain the low-pass filtered gain value of the PGA 360 as the nominal gain G. N When AGC 350 adjusts the gain of PGA 360 using multiple gain values ​​over a period of time, controller 142 is configured to low-pass filter the multiple gain values ​​to obtain the low-pass filtered gain value of PGA 360 as the nominal gain G. N The controller 142 is configured to store the low-pass filtered gain value of the PGA 360 in the memory 144.

[0050] The above references Figures 1 to 3 In the described implementation, the gain of the PGA 360 is considered to vary within a gain threshold when all components of the positioning device 160 are functioning fully. The PGA 360 has low-pass characteristics and a peak group delay at the band edge. As the gain of the PGA 360 increases, the amplification bandwidth of the PGA 360 decreases. If the gain of the PGA 360 increases to a high level, the information about the received signal in step 220 may include information about an estimate of the deviation caused by the variation in group delay on the received signal. In particular, the deviation estimate caused by the variation in group delay on positioning signals near the band edge can be used in method 200 to detect potential faults in the positioning device, such as the BeiDou B1D1 signal in the BeiDou Navigation Satellite System (BDS), the GLONASS L1OF and L2OF signals in the Global Navigation Satellite System (GLONASS), and the Galileo E5b signal in the Galileo positioning system.

[0051] In some implementations, the information about the received signal obtained in step 220 may include information about the inter-channel bias (ICB) estimate between the two channels of the positioning system. The detection threshold in step 240 includes a first ICB threshold and a second ICB threshold. The first ICB threshold is greater than the second ICB threshold. Determining whether a potential fault is detected in step 240 includes at least one of the following: comparing the ICB estimate with the first ICB threshold, or comparing the ICB estimate with the second ICB threshold; and determining that a potential fault is detected in response to one of the following: the comparison result is that the ICB estimate is greater than the first ICB threshold, or the comparison result is that the ICB estimate is less than the second ICB threshold.

[0052] For example, when the receiver 120 of the positioning device 160 receives a GLONASS signal, due to frequency-dependent distortion in the GLONASS signal, the signals of different GLONASS channels contain different group delays. For signal compensation and accurate positioning, the receiver 120 is configured to estimate the inter-channel delay (ICB) between two GLONASS channels caused by their different group delays. In other words, the receiver 120 is configured to estimate the ICB between the first GLONASS channel and the second GLONASS channel as the ICB of the first channel. The second GLONASS channel can be any of the GLONASS channels. The ICB estimation is an estimate of the per-channel delay.

[0053] When all components of the positioning device 160 are functioning fully, the ICB between the two GLONASS channels can vary, but within a range between the upper and lower limits. However, when a fault exists in one component of the positioning device 160, the fault may cause an abnormal ICB that is greater than the upper limit or less than the lower limit. Therefore, the fault detector 140 can be configured to implement method 200 to detect potential faults in one component of the positioning device 160, as described below.

[0054] Fault detector 140 is configured to obtain information about the ICB estimate between two GLONASS channels from navigation engine 128 of receiver 120 via connection 123. For example, the ICB estimate is the current ICB between the two GLONASS channels. C After the positioning device 160 is initialized and begins receiving GLONASS signals for positioning, the receiver 120 has a nominal ICB (Inter-Card Buffer). N When all components of the positioning device 160 are fully functional, the nominal ICB ICB NIt is the ICB between two GLONASS channels. When the positioning device 160 is operating normally and providing accurate location, the nominal ICB is... N It can be the average ICB.

[0055] The detection thresholds in step 240 include a first ICB threshold, which is equal to the nominal ICB. N Adding the first increment value dICB1 to ICB, that is, the first ICB threshold = ICB N +dICB1. For example, the first increment value dICB1 can be 3 cm or 5 cm per channel (cm / channel). The first increment value dICB1 is a first margin that allows for changes in ICB due to varying group delays in two different channels. The first ICB threshold is an upper limit on the ICB between two GLONASS channels.

[0056] The detection threshold in step 240 also includes a second ICB threshold, which is equal to the nominal ICB. N Subtracting the second increment value dICB2 of ICB, i.e., the second ICB threshold = ICB N –dICB2. For example, the second increment value dICB2 could be 2 cm or 3 cm per channel (cm / channel), which is a second margin that allows for changes in ICB due to varying group delays in two different channels. The second ICB threshold is the lower limit of the ICB between two GLONASS channels. The first ICB threshold (i.e., the upper limit of the ICB) is greater than the second ICB threshold (i.e., the lower limit of the ICB).

[0057] Determining whether a potential fault is detected at step 240 includes determining:

[0058]

[0059] Specifically, determining whether a potential fault is detected in step 240 includes: setting the current ICB. C Compared with the first ICB threshold ICB N +dICB1 is compared. Step 240 further includes: in response to the comparison result being that the current ICB is greater than the first ICB threshold, i.e., ICB C >ICB N +dICB1 indicates that a potential fault has been detected.

[0060] Step 240 includes: in response to the comparison result being that the current ICB is less than or equal to a first ICB threshold, setting the current ICB to the threshold value. C With the second ICB threshold ICB N–dICB2 is compared. Step 240 further includes: in response to the comparison result being that the current ICB is less than the second ICB threshold, i.e., ICB C <ICB N -dICB2 indicates that a potential fault has been detected.

[0061] Step 240 further includes: in response to the comparison result being that the current ICB is less than or equal to a first ICB threshold and greater than or equal to a second ICB threshold, determining that no potential fault has been detected.

[0062] In step 240, either the comparison between the current ICB and the first ICB threshold, or the comparison between the current ICB and the second ICB threshold, can be performed before the other. If one of the comparison results leads to the determination that a potential fault has been detected, the other comparison may not be performed.

[0063] In other words, fault detector 140 is configured to: if the current ICB ICB C Greater than the first ICB threshold ICB N +dICB1 or less than the second ICB threshold ICB N If –dICB2, it is determined that a potential fault has been detected in the positioning device 160. The fault detector 140 is configured to: if the current ICB ICB C Less than or equal to the first ICB threshold ICB N +dICB1 and greater than or equal to the second ICB threshold ICB N If –dICB2 is selected, it is determined that no potential fault was detected in the positioning device 160.

[0064] In some implementations, the nominal ICB in method 200 includes at least one of the following: a predetermined ICB value stored in at least one memory; an initial ICB value obtained from the initialization of the receiver of the positioning device; or a low-pass filtered ICB value.

[0065] For example, the controller 142 of the fault detector 140 can be configured to read a predetermined ICB value stored in the memory 144 as the nominal ICB. N The predetermined ICB value can be input by the user and stored in the memory 144. Alternatively, the predetermined ICB value can be the average ICB when the receiver 120 receives a signal for positioning in a previous time.

[0066] As another example, when receiver 120 is configured to execute an initialization procedure, controller 142 of fault detector 140 can be configured to acquire an initialization ICB value as the nominal ICB. NWhen receiver 120 executes the initialization procedure, navigation engine 128 is configured to estimate the ICB between the two GLONASS channels. Controller 142 is configured to use the initial ICB value as the nominal ICB. N The value is stored in memory 144. Alternatively, controller 142 can be configured to initialize the ICB value as the nominal ICB. N It is stored in a one-time programmable memory.

[0067] Alternatively, the controller 142 of the fault detector 140 can be configured to obtain the low-pass filtered ICB value as the nominal ICB. N When navigation engine 128 estimates multiple ICB values ​​between two GLONASS channels over a period of time, controller 142 is configured to low-pass filter the multiple ICB values ​​to obtain a low-pass filtered ICB value as the nominal value ICB1. N The controller 142 is configured to store the low-pass filtered ICB value in the memory 144.

[0068] In some implementations, the ICB estimate in method 200 includes an estimate of the group delay between two channels of the positioning system. For example, the ICB estimate in method 200 is an estimate of the group delay between two channels of GLONASS. Alternatively, the ICB estimate in method 200 may be an estimate of the group delay between two channels of the BeiDou or Galileo navigation satellite system.

[0069] Figure 4 This is a block diagram of an exemplary positioning device 400 consistent with embodiments of this disclosure. Figure 4 As shown, the positioning device 400 includes: a bandpass filter 410, a first matching component 422 and a second matching component 424, a first filter 432 and a second filter 434, a third matching component 442 and a fourth matching component 444, and a first Global Navigation Satellite System (GNSS) receiver 452 and a second Global Navigation Satellite System (GNSS) receiver 454. The bandpass filter 410, the first matching component 422, the first filter 432, the third matching component 442, and the first GNSS receiver 452 are sequentially connected to form a first receiver chain for receiving satellite signals in the first positioning system 460. The bandpass filter 410, the second matching component 424, the second filter 434, the fourth matching component 444, and the second GNSS receiver 454 are sequentially connected to form a second receiver chain for receiving satellite signals in the second positioning system 470.

[0070] The bandpass filter 410 is configured to receive signals via the input terminal 401 of the positioning device 400, filter signals of different frequencies from the first positioning system 460 and the second positioning system 470, and transmit the first system signal and the second system signal to the first receiving chain and the second receiving chain, respectively. In the first receiving chain, the first matching component 422, the first filter 432, and the third matching component 442 are configured to filter and process the first system signal so that the first GNSS receiver 452 can demodulate and decode messages from the satellites of the first positioning system 460. In the second receiving chain, the second matching component 424, the second filter 434, and the fourth matching component 444 are configured to filter and process the second system signal so that the second GNSS receiver 452 can demodulate and decode messages from the satellites of the second positioning system 470.

[0071] Positioning device 160, which serves as positioning device 400, may include two receiving chains. Therefore, fault detector 140 may be configured to implement method 200 to detect potential faults in positioning device 160 (similar to positioning device 400) having two receiving chains, as described below.

[0072] In some embodiments, the received signal in step 220 is a first received signal from a first positioning system (e.g., the first positioning system 460 of positioning device 400). The positioning device is configured to receive a second received signal from a second positioning system (e.g., the second positioning system 470 of positioning device 400). The information in step 220 includes an estimate of the inter-system bias (ISB) between the first and second positioning systems based on the first and second received signals. The detection threshold in step 240 includes a first ISB threshold and a second ISB threshold. The first ISB threshold is greater than the second ISB threshold. Determining whether a potential fault is detected at step 240 includes at least one of the following: comparing the ISB estimate with the first ISB threshold, or comparing the ISB estimate with the second ISB threshold; and determining that a potential fault is detected in response to one of the following: the comparison result is that the ISB estimate is greater than the first ISB threshold; or the comparison result is that the ISB estimate is less than the second ISB threshold.

[0073] For example, when the two receivers of the positioning device 160 receive GLONASS and Galileo signals, the GLONASS and Galileo signals contain different group delays due to frequency-dependent distortion at different frequencies. For instance, one receiver is configured to receive the GLONASS L1OF signal from 1598.1 MHz to 1605.4 MHz. The other receiver is configured to receive the Galileo E1BC signal at 1575 MHz. Alternatively, the receiver of the positioning device 160 can be configured to receive a 1575MHz GPS L1 signal, a 1559MHz BeiDou B1D1 signal, a 1575MHz Galileo E1BC signal, a 1598.1MHz to 1605.4MHz GLONASS L1OF signal, or a 1227MHz GPS L2C signal, a 1207MHz BeiDou B2I signal, a 1207MHz Galileo E5b signal, and 1242.9MHz and 1248.6MHz GLONASS L2OF signals. For signal compensation and accurate positioning, the positioning device 160 is configured to estimate the Inter-Stage Bias (ISB) between two signals from two GNSS systems caused by different group delays. The estimated ISB is the inter-GNSS deviation caused by variations in group delay in the signals from the two GNSS systems.

[0074] When all components of the positioning device 160 are functioning properly, the ISB between the two GNSS signals can vary, but will remain within a range between the upper and lower limits. However, when a component of the positioning device 160 malfunctions, the malfunction may cause an abnormal ISB that is greater than the upper limit or less than the lower limit. Therefore, the fault detector 140 can be configured to implement method 200 for detecting potential faults in a component of the positioning device 160, as described below.

[0075] Fault detector 140 is configured to obtain information about the ISB estimate between two signals from two receivers of positioning device 160 via connection 123. For example, the ISB estimate is the current ISB of the two signals from the two GNSS systems. C After the positioning device 160 is initialized, the positioning device 160 obtains the nominal ISB. N It then begins receiving signals from two GNSS systems for positioning. When all components of the positioning device 160 are fully functional, the nominal ISB (Inter-Standard Biological Component) is... N It is the ISB between two signals from two GNSS systems. The nominal ISB is defined as follows: when the positioning device 160 is operating normally and providing accurate positioning... N It can be the average ISB.

[0076] The detection threshold in step 240 includes a first ISB threshold, which is equal to the nominal ISB. N Adding the first increment value dISB1 to the ISB, that is, the first ISB threshold = ISB N +dISB1. For example, the first increment value dISB1 can be 5 cm or 6 cm per system (cm / system), which is the first margin that allows for changes in ISB due to varying group delays in the two signals of the two GNSS systems. The first ISB threshold is the upper limit of the ISB between the two signals of the two GNSS systems.

[0077] The detection threshold in step 240 also includes a second ISB threshold, which is equal to the nominal ISB. N Subtracting the second increment value dISB2 from the ISB, i.e., the second ISB threshold = ISB N –dISB2. For example, the second increment value dISB2 can be 4 cm or 5 cm per system (cm / system). The second increment value dISB2 is a second margin that allows for changes in ISB due to variations in group delay between the two signals of the two GNSS systems. The second ISB threshold is the lower limit of the ISB between the two signals of the two GNSS systems. The first ISB threshold (i.e., the upper limit of the ISB) is greater than the second ISB threshold (i.e., the lower limit of the ISB).

[0078] Determining whether a potential fault is detected at step 240 includes determining:

[0079]

[0080] Specifically, determining whether a potential fault is detected in step 240 includes: setting the current ISB. C Compared with the first ISB threshold, ISB N +dISB1 is compared. Step 240 further includes: in response to the comparison result being that the current ISB is greater than the first ISB threshold, i.e., ISB... C >ISB N +dISB1 indicates that a potential fault has been detected.

[0081] Step 240 includes: in response to the comparison result being that the current ISB is less than or equal to a first ISB threshold, setting the current ISB to 1.5. C With the second ISB threshold ISB N –dISB2 is compared. Step 240 further includes: in response to the comparison result being that the current ISB is less than the second ICB threshold, i.e., ISB C <ISB N-dISB2 indicates that a potential fault has been detected.

[0082] Step 240 further includes: in response to the comparison result being that the current ISB is less than or equal to a first ISB threshold and greater than or equal to a second ISB threshold, i.e., ISB N -dISB2≤ISB C ≤ISB N +dISB1 indicates that no potential fault was detected.

[0083] In step 240, either the comparison between the current ISB and the first ISB threshold, or the comparison between the current ISB and the second ISB threshold, can be performed before the other. If one of the comparisons leads to a determination that a potential fault has been detected, the other comparison may not be performed. Alternatively, if one of the comparisons leads to a determination that a potential fault has been detected, the other comparison may still be performed.

[0084] In other words, fault detector 140 is configured to: if the current ISB ISB C ISB greater than the first ISB threshold N +dISB1 or less than the second ISB threshold ISB N If –dISB2, it is determined that a potential fault has been detected in the positioning device 160. The fault detector 140 is configured to detect a potential fault if the current ISB is ISB2. C Less than or equal to the first ISB threshold ISB N +dISB1 and greater than or equal to the second ISB threshold ISB N If –dISB2 is selected, it is determined that no potential fault was detected in the positioning device 160.

[0085] In some implementations, the nominal ISB in method 200 includes at least one of the following: a predetermined ISB value stored in at least one memory; an initial ISB value obtained from the initialization of the receiver of the positioning device; or a low-pass filtered ISB value.

[0086] For example, the controller 142 of the fault detector 140 is configured to read a predetermined ISB value stored in the memory 144 as the nominal ISB. N The predetermined ISB value can be input by the user and stored in memory 144. Alternatively, the predetermined ISB value can be the average ISB when two receivers receive signals for positioning in a previous time period.

[0087] As another example, when the two receivers of the positioning device 160 are configured to perform an initialization procedure, the controller 142 of the fault detector 140 can be configured to acquire the initialization ISB value as the nominal ISB. NWhen the two receivers perform the initialization procedure, they are configured to estimate the ISB between two signals from the two GNSS systems. Controller 142 is configured to use the initial ISB value as the nominal ISB. N The value is stored in memory 144. Alternatively, controller 142 can be configured to use the initial ISB value as the nominal ISB. N Stored in a one-time programmable memory

[0088] Alternatively, the controller 142 of the fault detector 140 can be configured to obtain the low-pass filtered ISB value as the nominal ISB. N When two receivers estimate multiple ISB values ​​between two GNSS systems over a period of time, controller 142 is configured to low-pass filter the multiple ISB values ​​to obtain a low-pass filtered ISB value as the nominal ISB. N Controller 142 is configured to store the low-pass filtered ISB value in memory 144.

[0089] In some implementations, the received signal in step 220 is a first received signal from a first positioning system. The positioning device (e.g., positioning device 160) is configured to receive multiple received signals from multiple positioning systems, including the first positioning system. The received signals include the first received signal. The information in step 220 includes multiple Global Navigation Satellite System (Multi-GNSS) estimates. The Multi-GNSS estimates include multiple inter-system bias (ISB) estimates corresponding to multiple positioning system pairs. The detection thresholds in step 240 include a first Multi-GNSS ISB threshold, a second Multi-GNSS ISB threshold, a first system quantity threshold, and a second system quantity threshold. The first Multi-GNSS ISB threshold includes multiple first ISB thresholds corresponding to paired positioning systems. The second Multi-GNSS ISB threshold includes multiple second ISB thresholds corresponding to multiple positioning system pairs. Each first ISB threshold is greater than its corresponding second ISB threshold. Determining whether a potential fault is detected in step 240 includes: (i) at least one of the following: (a) comparing the ISB estimate with a plurality of first ISB thresholds; and determining that the multi-GNSS ISB estimate is greater than the first multi-GNSS ISB threshold when the number of ISB estimates greater than the first ISB threshold is greater than the first system quantity threshold; or (b) comparing the ISB estimate with a plurality of second ISB thresholds; and determining that the multi-GNSS ISB estimate is less than the second multi-GNSS ISB threshold when the number of ISB estimates less than the second ISB threshold is greater than the second system quantity threshold; and (ii) determining that a potential fault is detected in response to at least one of the following: determining that the multi-GNSS ISB estimate is greater than the first multi-GNSS ISB threshold; or determining that the multi-GNSS ISB estimate is less than the second multi-GNSS ISB threshold.

[0090] For example, positioning device 160 is configured to receive the above reference. Figure 1 The received GLONASS signal is a first GLONASS signal from a first positioning system (i.e., a GLONASS system). The two receivers of the positioning device 160 can be configured to receive the first GLONASS signal and the first Galileo signal, respectively. Due to frequency-dependent distortion at different frequencies, the first GLONASS signal and the first Galileo signal contain different group delays. For signal compensation and accurate positioning, the positioning device 160 is configured to estimate a first ISB between the two first signals from the two GNSS systems caused by the different group delays. The estimated first ISB is the first inter-GNSS deviation caused by the group delay variation in the first GLONASS and first Galileo signals.

[0091] The positioning device 160 has two receivers configured to receive a second GLONASS signal and a second Galileo signal, respectively. Similarly, the positioning device 160 is configured to estimate a second ISB between the second GLONASS signal and the second Galileo signal due to different group delays. In this way, the positioning device 160 is configured to receive multiple received signals from the GLONASS system and the Galileo system (including the first positioning system, i.e., the GLONASS system).

[0092] The positioning device 160 has two receivers configured to receive a third GLONASS signal and a third Galileo signal, respectively. Similarly, the positioning device 160 is configured to estimate a third ISB between the third GLONASS signal and the third Galileo signal due to different group delays. In this way, the positioning device 160 is configured to receive multiple received signals from the GLONASS system and the Galileo system (including the first positioning system, i.e., the GLONASS system). The positioning device 160 is configured to estimate multiple ISBs corresponding to multiple pairs of GLONASS and Galileo system pairs.

[0093] Alternatively, the two receivers of positioning device 160 can also be configured to receive Galileo and BeiDou signals respectively. Positioning device 160 is configured to estimate the ISB between the Galileo and BeiDou signals caused by different group delays. Furthermore, the two receivers of positioning device 160 can be configured to receive BeiDou signals and Global Positioning System (GPS) signals respectively. Positioning device 160 is configured to estimate the ISB between the BeiDou and GPS signals caused by different group delays. In this way, the multiple received signals received by positioning device 160 can come from multiple positioning systems (e.g., GLONASS, Galileo, BeiDou, and GPS). Therefore, positioning device 160 is configured to estimate multiple ISBs corresponding to multiple positioning system pairs.

[0094] Similar to ISB in equation (3) C When all components of the positioning device 160 are functioning properly, each of the multiple ISBs between the two GNSS signals can vary, but will remain within a range between the upper and lower limits. However, a fault in one component of the positioning device 160 may cause an abnormal ISB that is greater than the upper limit or less than the lower limit. Therefore, the fault detector 140 can be configured to implement method 200 for detecting potential faults in one component of the positioning device 160, as described below.

[0095] Fault detector 140 is configured to obtain information about multiple inter-system bias (ISB) estimates corresponding to multiple positioning system pairs from one or more receivers via connection 123. For example, fault detector 140 is configured to obtain multiple ISB estimates corresponding to multiple positioning system pairs. For example, the multiple ISB estimates are multiple current ISB signal ISBs of two GNSS systems. Ci (i = 0, 1, 2, ..., SP-1), where SP is the total number of positioning system pairs. One of the positioning system pairs can be two positioning systems that are the same as or different from the other in the pair. Multiple current ISBs Ci They are collectively defined as multi-GNSS ISB estimates.

[0096] After the positioning device 160 is initialized and begins receiving signals from two GNSS systems for positioning, the positioning device 160 acquires multiple nominal ISBs. Ni (i = 0, 1, 2, ..., SP-1). Multiple nominal ISBs (ISBs) are used when all components of the positioning device 160 are fully functional. Ni The nominal ISB is the signal strength between multiple GNSS system pairs. When the positioning device 160 is operating normally and providing accurate positioning, the nominal ISB is... Ni It can be the average ISB.

[0097] The detection threshold in step 240 includes multiple first ISB thresholds, each of which is equal to the nominal ISB. Ni In addition to the multiple first increment values ​​dISB of ISB 1i That is, the first ISB threshold of the i-th GNSS system pair = ISB Ni +dISB 1i (i = 0, 1, 2, ..., SP-1). For example, multiple first increment values ​​dISB for each system pair. 1i These first increment values, 4 cm or 5 cm (cm / pair), are multiple first margins that allow for variations in the ISB across multiple GNSS system pairs due to varying group delays. The multiple first ISB thresholds are respectively upper limits on the ISB between two GNSS signals in each GNSS system pair. Ni +dISB 1i (i = 0, 1, 2, ..., SP-1) are collectively defined as the first multi-GNSS threshold.

[0098] The detection threshold in step 240 also includes a plurality of second ISB thresholds, which are equal to the nominal ISB. NiSubtract multiple second increment values ​​dISB from ISB 2i That is, the second ISB threshold = ISB Ni –dISB 2i (i = 0, 1, 2, ..., SP-1). For example, multiple second increment values ​​dISB 2i The multiple second increment values ​​can be 4 cm or 5 cm (cm / system) per pair, and each second increment value represents a multiple second margin that allows for variations in the ISB of the multiple GNSS system pairs due to varying group delays. The multiple second ISB thresholds are lower limits on the ISB between the two GNSS signals in each GNSS system pair. Ni –dISB 2i (i = 0, 1, 2, ..., SP-1) are collectively defined as the second multi-GNSS threshold. Multiple first ISB thresholds (i.e., the upper limit of ISB) are each greater than multiple second ISB thresholds (i.e., the lower limit of ISB).

[0099] Determining whether a potential fault is detected at step 240 includes determining:

[0100]

[0101] Determining whether a potential fault is detected at step 240 includes: if neither SN1 pairs nor SN2 pairs according to the above conditions are achieved, then it is determined that no potential fault is detected, where SN1 and SN2 are the first system quantity threshold and the second system quantity threshold.

[0102] Specifically, determining whether a potential fault is detected in step 240 includes: setting the current ISB. Ci Each with multiple first ISB thresholds ISB Ni +dISB 1i The comparison is performed. Step 240 further includes: in response to the comparison result being a first number of ISB estimates greater than a first ISB threshold greater than or equal to a first system number threshold SN1, that is, for SN1 or more pairs, the ISB... Ci >ISB Ni +dISB 1i The estimated value of the multiple GNSS (multi-GNSS) ISB is determined to be greater than the first multiple GNSS ISB threshold.

[0103] Step 240 further includes: in response to the comparison result being a first number less than a first pair of number thresholds SN1, determining that the multi-GNSS ISB estimate is less than a first multi-GNSS ISB threshold.

[0104] Step 240 includes: in response to the comparison result being that the ISB estimate is greater than a first ISB threshold and less than a first pair of quantity thresholds SN1, setting the current ISB to ISB. Ci Each with multiple second ISB thresholds ISB Ni –dISB 2i A comparison is performed. Step 240 further includes: in response to the comparison result being a second number of ISB estimates less than a second ISB threshold that are greater than or equal to a second system number threshold SN2, i.e., for SN2 or more pairs, the ISB... Ci <ISB Ni -dISB 2i The multi-GNSS ISB estimate was determined to be less than the second multi-GNSS ISB threshold.

[0105] Step 240 further includes: in response to the comparison result being that the ISB estimate is less than the second number of the second ISB threshold SN2, determining that the multi-GNSS ISB estimate is greater than the second multi-GNSS ISB threshold.

[0106] In some implementations, in step 240, either the comparison between the current ISB and a first ISB threshold or the comparison between the current ISB and a second ISB threshold can be performed before the other. When one of the comparisons is performed, the other comparison may not be performed. Alternatively, when one of the comparisons is performed, the other comparison may still be performed.

[0107] In addition, step 240 further includes determining that a potential fault has been detected in response to at least one of the following: determining that the multi-GNSS ISB estimate is greater than a first multi-GNSS ISB threshold; or determining that the multi-GNSS ISB estimate is less than a second multi-GNSS ISB threshold.

[0108] In other words, the fault detector 140 is configured such that: if the comparison result is that the ISB estimate is greater than a first ISB threshold, and the first number is greater than or equal to a first system quantity threshold SN1, that is, for SN1 or more pairs, the ISB... Ci >ISB Ni +dISB 1i If the comparison result is that the ISB estimate is less than a second ISB threshold, and the second number is greater than or equal to a second system quantity threshold SN2, then a potential fault is determined to be detected in the positioning device 160. The fault detector 140 is configured to: if the comparison result is that the ISB estimate is less than a second number of times the second ISB threshold is greater than or equal to a second system quantity threshold SN2, that is, for SN2 or more pairs, the ISB... Ci <ISB Ni -dISB 2i If so, it is determined that a potential fault was detected in the positioning device 160.

[0109] In some implementations, fault detector 140 may be configured to compare ISB estimates with a first ISB threshold or a second ISB threshold until SN1 or SN2 pairs are achieved as described in equation (4), and to determine that a potential fault has been detected in positioning device 160. Fault detector 140 may not be configured to compare the remaining ISB estimates with the remaining first ISB threshold or second ISB threshold.

[0110] In some implementations, fault detector 140 is configured to compare an ISB estimate with one or more first ISB thresholds and one or more second ISB thresholds until a third system quantity threshold SN3 is reached. Fault detector 140 is configured to determine that a potential fault has been detected in positioning device 160 if (a) the sum of a first number of ISB estimates greater than the first ISB threshold and (b) the sum of a second number of ISB estimates less than the second ISB threshold is greater than or equal to the third system quantity threshold SN3.

[0111] In some implementations, the nominal ISB in method 200 includes at least one of the following: a predetermined ISB value stored in at least one memory; an initial ISB value obtained from the initialization of the positioning device; or a low-pass filtered ISB value, similar to the nominal ISB described in reference equation (3) above.

[0112] Figure 5 This is a block diagram of an exemplary antenna subsystem 500 of a positioning device consistent with embodiments of this disclosure. Antenna subsystem 500 is a dual-band GNSS antenna subsystem. Figure 5 As shown, the antenna subsystem 500 includes two antenna receiving paths. The first antenna receiving path includes, in sequence, antennas 501 and 502, a first hybrid coupler 512, a first resistor 513, a first filter 522, a first matching component 532, a first low-noise amplifier (LNA) 533, a second matching component 542, a second filter 552, a third matching component 562, a second LNA 563, a fourth matching component 572, and a duplexer 580. The second antenna receiving path includes, in sequence, antennas 503 and 504, a second hybrid coupler 514, a second resistor 515, a third filter 524, a fifth matching component 534, a third LNA 535, a sixth matching component 544, a fourth filter 554, a seventh matching component 564, a fourth LNA 565, an eighth matching component 574, and a duplexer 580.

[0113] The first antenna receiving path and the second antenna receiving path are configured to receive signals from two frequency bands respectively and output the signal from one of the two frequency bands to, for example, the input terminal 101 of the positioning device 160 via the output 505 of the antenna subsystem 500.

[0114] When the dual-frequency GNSS antenna subsystem 500 is connected to the input 101 of the positioning device 160, the positioning device 160 becomes a dual-frequency positioning device. The fault detector 140 can be configured to implement method 200 for detecting potential faults in the dual-frequency positioning device, as described below.

[0115] In some implementations, the information in step 220 includes an estimate of the inter-band offset (IBB) between the two frequency bands of the positioning system. The detection threshold in step 240 includes a first IBB threshold and a second IBB threshold. The first IBB threshold is greater than the second IBB threshold. Determining whether a potential fault is detected in step 240 includes at least one of the following: comparing the IBB estimate with the first IBB threshold, or comparing the IBB estimate with the second IBB threshold; and determining that a potential fault is detected in response to one of the following: a comparison result where the IBB estimate is greater than the first IBB threshold; or a comparison result where the IBB estimate is less than the second IBB threshold.

[0116] For example, when positioning device 160 is configured to receive GPS signals in the L1 and L2 frequency bands via dual-band antenna subsystem 500, the GPS L1 and L2 signals contain different group delays due to frequency correlation distortion of the signals in the two different frequency bands. For signal compensation and accurate positioning, positioning device 160 is configured to estimate the IBB between the two signals in the GPS L1 and L2 frequency bands caused by the different group delays.

[0117] When all components of the positioning device 160 are functioning properly, the IBB between the two signals in the two frequency bands can vary, but will remain within the range between the upper and lower limits. However, when a fault exists in one component of the positioning device 160, the fault may cause an abnormal IBB that is greater than the upper limit or less than the lower limit. Therefore, as described below, the fault detector 140 can be configured to implement method 200 for detecting potential faults in one component of the positioning device 160.

[0118] Fault detector 140 is configured to obtain information about the IBB estimate between two signals on two frequency bands from receiver 120 via connection 123. For example, the IBB estimate is the current IBB BBB of two signals on GPS L1 and L2 frequency bands. CAfter the positioning device 160 is initialized and begins receiving signals on the GPS L1 and L2 bands for positioning, the positioning device 160 obtains a nominal IBB (Independent Bicycle Bead) rating. N When all components of the positioning device 160 are fully functional, the nominal IBB (Independent Biological Scale) is... N It is the IBB between two signals on the GPS L1 and L2 frequency bands. The nominal IBB is defined as the distance between the two signals when the positioning device is operating normally and providing accurate location. N It could be the average IBB.

[0119] Fault detector 140 is configured to obtain a first IBB threshold from memory 144, the first IBB threshold being equal to the nominal IBB IBB. N Adding the first increment value dIBB1 of IBB, that is, the first IBB threshold = IBB N +dIBB1. For example, the first increment value dBB1 can be 2 cm or 3 cm per band (cm / band). The first increment value dBB1 is a first margin that allows for changes in IBB due to variations in group delay between the two signals in the GPS L1 and L2 bands. The first IBB threshold is the upper limit of the IBB between the two signals in the GPS L1 and L2 bands.

[0120] Fault detector 140 is configured to obtain a second IBB threshold from memory 144, the second IBB threshold being equal to the nominal IBB IBB. N Subtract the second increment value of IBB, dIBB2, that is, the second IBB threshold = IBB N –dIBB2. For example, the second increment value of IBB, dIBB2, can be 4 or 5 centimeters per band (cm / band). The second increment value, dIBB2, is a second margin that allows for variations in IBB due to changes in group delay between the two signals in the GPS L1 and L2 bands. The second IBB threshold is the lower limit of the IBB between the two signals in the GPS L1 and L2 bands. The first IBB threshold (i.e., the upper limit of IBB) is greater than the second IBB threshold (i.e., the lower limit of IBB).

[0121] Determining whether a potential fault is detected at step 240 includes determining:

[0122]

[0123] Specifically, determining whether a potential fault is detected in step 240 includes: setting the current IBB (Independent IBB). C Compared with the first IBB threshold IBB N+dIBB1 is compared. Step 240 further includes: in response to the comparison result being that the current IBB is greater than the first IBB threshold, i.e., IBB... C >IBB N +dIBB1 indicates that a potential fault has been detected.

[0124] Step 240 includes: in response to the comparison result being that the current IBB is less than or equal to the first IBB threshold, setting the current IBB to the appropriate threshold. C With the second IBB threshold IBB N –dIBB2 is compared. Step 240 further includes: in response to the comparison result being that the current IBB is less than the second IBB threshold, i.e., IBB C <IBB N -dIBB2 indicates that a potential fault has been detected.

[0125] Step 240 further includes: in response to the comparison result being that the current IBB is less than or equal to a first IBB threshold and greater than or equal to a second IBB threshold, i.e., IBB N -dIBB2≤IBB C ≤IBB N +dIBB1 indicates that no potential fault was detected.

[0126] In step 240, either the comparison between the current IBB and the first IBB threshold, or the comparison between the current IBB and the second IBB threshold, can be performed before the other. If one of the comparisons leads to a determination that a potential fault has been detected, the other comparison may not be performed. Alternatively, if one of the comparisons leads to a determination that a potential fault has been detected, the other comparison may still be performed.

[0127] In other words, fault detector 140 is configured to: if the current IBB IBB C Greater than the first IBB threshold IBB N +dIBB1 or less than the second IBB threshold IBB N If –dIBB2, then a potential fault is detected in the positioning device 160. The fault detector 140 is configured to: if the current IBB IBB C Less than or equal to the first IBB threshold IBB N +dIBB1 and greater than or equal to the second IBB threshold IBB N If –dIBB2 is selected, it is determined that no potential fault was detected in the positioning device 160.

[0128] In some implementations, the nominal IBB in method 200 includes: a predetermined IBB value stored in at least one memory; an initial IBB value obtained from the initialization of the receiver of the positioning device; or a low-pass filtered IBB value.

[0129] For example, the controller 142 of the fault detector 140 is configured to read a predetermined IBB value stored in the memory 144 as the nominal IBB IBB. N The user can input a predetermined IBB value and store it in memory 144. Alternatively, the predetermined IBB value can be an average IBB when the receiver 120 receives a signal for positioning in a previous time.

[0130] As another example, when receiver 120 is configured to execute an initialization procedure, controller 142 of fault detector 140 can be configured to acquire an initial IBB value as the nominal IBB IBB. N When receiver 120 executes the initialization procedure, receiver 120 is configured to estimate the IBB between two signals on two frequency bands of the positioning system. Controller 142 is configured to use the initialized IBB value as the nominal IBB. N The value is stored in memory 144. Alternatively, controller 142 can be configured to initialize the IBB value as the nominal IBB IBB. N It is stored in a one-time programmable memory.

[0131] Alternatively, the controller 142 of the fault detector 140 can be configured to obtain the low-pass filtered IBB value as the nominal IBB. N When receiver 120 estimates multiple IBB values ​​between two frequency bands of the bit system over a period of time, controller 142 is configured to low-pass filter the multiple IBB values ​​to obtain a low-pass filtered IBB value as the nominal IBB1BB. N Controller 142 is configured to store the low-pass filtered IBB value in memory 144.

[0132] In some implementations, the IBB estimate in method 200 includes a plurality of IBB band estimates corresponding to a plurality of band pairs. The first IBB threshold used in method 200 includes a plurality of first IBB band thresholds corresponding to a plurality of band pairs. The second IBB threshold used in method 200 includes a plurality of second IBB band thresholds corresponding to a plurality of band pairs. Comparing the IBB estimate with the first IBB threshold in method 200 includes: comparing each of the plurality of IBB band estimates with the plurality of first IBB band thresholds; and determining that the IBB estimate is greater than the first IBB threshold when the number of IBB band estimates greater than the first IBB band threshold is greater than a first band quantity threshold. Comparing the IBB estimate with the second IBB threshold in method 200 includes: comparing each of the IBB band estimates with the plurality of second IBB band thresholds; and determining that the IBB estimate is less than the second IBB threshold when the number of IBB band estimates less than the second IBB band threshold is greater than a second band quantity threshold.

[0133] For example, positioning device 160 is configured to estimate multiple IBB band estimates corresponding to multiple frequency band pairs of the GPS system. Fault detector 140 is configured to obtain multiple IBB band estimates corresponding to multiple frequency band pairs of the GPS system. For example, the multiple IBB band estimates are multiple current IBB band estimates of signals on GPS L1 and L2 frequency bands. Ci (i = 0, 1, 2, ..., BP-1), where BP is the total number of band pairs. One of the band pairs can include the same or different bands as the other in the band pair. Multiple current IBB band estimates. Ci (i = 0, 1, 2, ..., BP-1) are collectively defined as the IBB estimate value estimated by the positioning device 160.

[0134] After the positioning device 160 is initialized and begins receiving signals on the GPS band pair, the positioning device 160 obtains multiple nominal IBB band estimates. Ni (i = 0, 1, 2, ..., BP-1). Multiple nominal IBB band estimates IBB when all components of the positioning device 160 are fully functional. Ni The IBB is the signal between multiple GPS frequency band pairs. The nominal IBB band estimate is IBB when the positioning device 160 is operating normally and providing accurate location. Ni It could be the average IBB.

[0135] Fault detector 140 is configured to obtain a plurality of first IBB band thresholds from memory 144, the plurality of first IBB band thresholds being equal to the nominal IBB band estimated IBB.Ni In addition to the multiple first increment values ​​dIBB in the IBB band 1i That is, the first IBB band threshold of the i-th band pair = IBB Ni +dIBB 1i (i = 0, 1, 2, ..., BP-1). For example, multiple first increment values ​​dBB in the IBB band. 1i The values ​​can be 2 cm or 3 cm per frequency band pair (cm / pair), and the plurality of first increment values ​​dBB 1i These are multiple first margins that allow for variations in the IBB (Independent Broadband Scale) across multiple band pairs due to varying group delays. The multiple first IBB band thresholds are the upper limits of the IBB between the signals of the two bands in each band pair. Ni +dIBB 1i (i = 0, 1, 2, ..., BP-1) are collectively defined as the first IBB threshold.

[0136] Fault detector 140 is also configured to obtain a plurality of second IBB band thresholds from memory 144, the plurality of second IBB band thresholds being equal to the nominal IBB band estimate IBB. Ni Subtract each of the second increment values ​​dIBB in the IBB band. 2i That is, the second IBB band threshold = IBB Ni –dIBB 2i (i = 0, 1, 2, ..., BP-1). For example, multiple second increment values ​​dBB in the IBB band. 2i The multiple second increment values ​​(dIBB) can be 2 cm or 3 cm per frequency band pair. 2i These are multiple second margins that allow for variations in the IBB (Independent Broadband Scale) across multiple band pairs due to varying group delays. The multiple second IBB band thresholds are the lower bounds of the IBB between the signals of the two bands in each band pair. Ni –dIBB 2i (i = 0, 1, 2, ..., BP-1) are collectively defined as the second IBB threshold. Multiple first IBB band thresholds (i.e., the upper limit of IBB) are each greater than multiple second IBB band thresholds (i.e., the lower limit of IBB).

[0137] Determining whether a potential fault is detected at step 240 includes determining:

[0138]

[0139] Determining whether a potential fault is detected at step 240 includes: if neither BN1 pairs nor BN2 pairs according to the above conditions are realized, it is determined that no potential fault is detected, where BN1 and BN2 are the first frequency band quantity threshold and the second frequency band quantity threshold.

[0140] Specifically, determining whether a potential fault is detected in step 240 includes: estimating the current IBB band value as IBB. Ci Each with multiple first IBB band thresholds IBB Ni +dIBB 1i A comparison is performed. Step 240 further includes: in response to the comparison result being that the number of IBB band estimates greater than the first IBB band threshold is greater than or equal to the first band number threshold BN1, that is, for BN1 or more pairs, the IBB band estimate is greater than or equal to the first band number threshold BN1. Ci >IBB Ni +dIBB 1i The estimated IBB value is determined to be greater than the first ISB threshold.

[0141] Step 240 further includes: in response to the comparison result being that the number of IBB band estimates greater than the first IBB band threshold is less than the first band number threshold BN1, determining that the IBB estimate is less than the first IBB threshold.

[0142] Step 240 includes: in response to the comparison result being that the number of IBB band estimates greater than the first IBB band threshold is less than the first band quantity threshold BN1, the current IBB band estimate is set to IBB. Ci With the second ISB band threshold IBB Ni –dIBB 2i A comparison is performed. Step 240 further includes: in response to the comparison result being that the number of IBB band estimates less than the second ISB band threshold is greater than or equal to the second band number threshold BN2, that is, for BN2 or more pairs, IBB... Ci <IBB Ni -dIBB 2i The estimated IBB value is determined to be less than the second IBB threshold.

[0143] Step 240 further includes: in response to the comparison result being that the number of IBB band estimates less than the second IBB band threshold is less than the second band number threshold BN2, determining that the IBB estimate is greater than the second IBB threshold.

[0144] In some implementations, in step 240, either the comparison between the current IBB band estimate and the first IBB band threshold, or the comparison between the current IBB band estimate and the second IBB band threshold, can be performed before the other. When one of the comparisons is performed, the other comparison may not be performed. Alternatively, when one of the comparisons is performed, the other comparison may still be performed.

[0145] In addition, step 240 further includes determining that a potential fault has been detected in response to at least one of the following: determining that the IBB estimate is greater than a first IBB threshold; or determining that the IBB estimate is less than a second IBB threshold.

[0146] In other words, the fault detector 140 is configured such that: if the comparison result shows that the number of IBB band estimates greater than the first IBB band threshold is greater than or equal to the first band quantity threshold BN1, that is, for BN1 or more pairs, the fault detector 140 is configured to: Ci >IBB Ni +dIBB 1i The system determines that a potential fault has been detected in the positioning device 160. The fault detector 140 is configured to: if the comparison result shows that the number of IBB band estimates less than a second ISB band threshold is greater than or equal to a second band number threshold BN2, i.e., for BN2 or more pairs, IBB... Ci <IBB Ni -dIBB 2i A potential fault was detected in the positioning device 160.

[0147] In some implementations, fault detector 140 may be configured to compare the IBB band estimate with a first IBB band threshold or a second IBB band threshold until BN1 or BN2 pairs are achieved as described in equation (6), and determine that a potential fault has been detected in the location. Fault detector 140 may also be configured not to compare the remaining IBB band estimate with the remaining first IBB band threshold or second IBB band threshold.

[0148] In some implementations, the fault detector 140 is configured to compare an IBB band estimate with one or more first IBB band thresholds and one or more second IBB band thresholds until a third band quantity threshold BN3 is reached. The fault detector 140 is configured to determine that a potential fault has been detected in the positioning device 160 if (a) the sum of a first number of IBB band estimates greater than the first IBB band threshold and (b) the sum of a second number of IBB band estimates less than the second IBB band threshold is greater than or equal to the third band quantity threshold BN3.

[0149] In some implementations, the nominal IBB band estimate in method 200 includes at least one of the following: a predetermined IBB band value stored in at least one memory; an initial IBB band value obtained from the initialization of the positioning device; or a low-pass filtered IBB band value, similar to the nominal IBB described in reference equation (5) above.

[0150] In some implementations, the information in step 220 includes a gain control parameter and a deviation estimate. The detection threshold in step 240 includes a gain threshold, a first deviation threshold, and a second deviation threshold. The first deviation threshold is greater than the second deviation threshold. Determining whether a potential fault is detected in step 240 includes: comparing the gain control parameter to the gain threshold; comparing the deviation estimate to the first deviation threshold or to the second deviation threshold, at least one of the following: the comparison result is that the gain control parameter is greater than the gain threshold; and (i) the comparison result is that the deviation estimate is greater than the first deviation threshold or (ii) the comparison result is that the deviation estimate is less than the second deviation threshold.

[0151] For example, fault detector 140 is configured to: obtain the current gain G of PGA 360 between two GLONASS channels. c And the current ICB ICB C Information such as reference equations (1) and (2) and Figures 1 to 3 As described. Fault detector 140 is configured to obtain a gain threshold from memory 144, which is equal to the nominal gain G. N Adding the gain increment dG, i.e., the gain threshold = G N +dG. Fault detector 140 is also configured to obtain a first ICB threshold and a second ICB threshold from memory 144, the first ICB threshold being equal to the nominal ICB. N Adding the first incremental value dICB1, that is, the first ICB threshold = ICB N +dICB1, the second ICB threshold is equal to the nominal ICB. N Subtract the second increment value dICB2, that is, the second ICB threshold = ICB N –dICB2, as in reference equations (1) and (2) and Figures 1 to 3 The first ICB threshold (i.e., the upper limit of ICB) is greater than the second ICB threshold (i.e., the lower limit of ICB).

[0152] Fault detector 140 is configured to: measure the current gain G of PGA 360 c With gain threshold G N+dG comparison. Fault detector 140 is also configured to: compare the current ICB ICB. C Compared with the first ICB threshold ICB N +dICB1 is compared, and / or the current ICB ICB is compared. C With the second ICB threshold ICB N –dICB2 is compared. Fault detector 140 is configured to determine a potential fault detected in response to the following: the comparison result is the current gain G of PGA 360. c Greater than the gain threshold G N +dG, and (i) the comparison result is the current ICB ICB C Greater than the first ICB threshold ICB N +dICB1 or (ii) The comparison result is the current ICB ICB C Less than the second ICB threshold ICB N One of –dICB2.

[0153] In some implementations, the fault detector 140 may be configured to obtain information about one or more of the following: the current gain G of the PGA 360. c The current ICB between the two channels C The current ISB between two signals from two GNSS systems C And / or the current IBB between two signals in two frequency bands C As shown in the above reference equations (1) to (6) and Figures 1 to 5 As described, the fault detector 140 can be configured to determine that a potential fault has been detected in response to the satisfaction of two or more conditions in equations (1) to (6).

[0154] In some implementations, the information in step 220 includes: an estimate of at least one of the input spectra of the positioning device, or a obtained pseudorange measurement residual for a given estimated location, the obtained pseudorange measurement residual having an estimation bias based on the received signal.

[0155] For example, fault detector 140 is configured to obtain an estimate of the input spectrum of positioning device 160. The input spectrum includes the standard deviation of the ADC sampling of positioning device 160. AGC 350 is configured to control the gain of PGA 360 to keep the standard deviation of ADC sampling constant, thereby supporting the dynamic range of receiver 120. AGC 350 can control the gain of PGA 360 to keep the standard deviation of ADC sampling substantially constant when all components of positioning device 160 are fully functional.

[0156] When a fault exists in a component of the positioning device 160, the fault may cause an abnormal standard deviation in the ADC samples. Due to the fault in a component of the positioning device 160, the abnormal standard deviation in the ADC samples may exceed a standard deviation threshold. Therefore, the fault detector 140 may implement method 200 to detect a potential fault in a component of the positioning device 160 based on the standard deviation of the ADC samples and the standard deviation threshold, similar to the steps described above for fault detection based on the gain and gain threshold of the PGA 360 and equation (1). Alternatively, the fault detector 140 may be configured to detect potential faults based on the standard deviation in the ADC samples, the gain of the PGA 360, the standard deviation threshold, and the gain threshold. The latter alternative may provide a shorter fault detection response time.

[0157] As another example, fault detector 140 can be configured to obtain a pseudorange measurement residual for a given estimated location, the pseudorange measurement residual having an estimation bias based on the received signal. When positioning device 160 is configured to estimate for a given location, the individual measurements may include the obtained pseudorange measurement residual due to noise and / or interference. When all components of positioning device 160 are fully functional, it is expected that the pseudorange measurement residual increases or decreases linearly at different frequencies (i.e., different channels).

[0158] When a fault exists in a component of the positioning device 160, the fault may cause an abnormal increase in the absolute value of the pseudorange measurement residual. Before the receiver 120 adjusts the ICB estimate to minimize the pseudorange measurement residual, the absolute value of the abnormal pseudorange measurement residual may exceed the residual threshold due to the fault in a component of the positioning device 160. Therefore, the fault detector 140 may implement method 200 to detect a potential fault in a component of the positioning device 160 based on the obtained pseudorange measurement residual and the residual threshold, similar to the steps described above for fault detection based on the gain and gain threshold of PGA 360 and equation (1).

[0159] Another aspect of this disclosure relates to a non-transitory processor-readable medium storing instructions that, when executed, cause one or more processors to perform the methods described above. The processor-readable medium may include volatile or non-volatile, magnetic, semiconductor, magnetic tape, optical, removable, non-removable, or other types of processor-readable media or processor-readable storage devices. For example, as disclosed, the processor-readable medium may be a storage device or memory module on which processor instructions are stored. In some embodiments, the processor-readable medium may be a disk or flash drive on which processor instructions are stored.

[0160] It will be understood that this disclosure is not limited to the exact constructions described above and illustrated in the accompanying drawings, and that various modifications and changes may be made without departing from the scope of the invention. The scope of this application should be intended to be limited only by the appended claims.

Claims

1. An apparatus for detecting a potential fault in a positioning device, the apparatus comprising: at least one memory for storing instructions; and at least one controller configured to execute the instructions to perform operations comprising: obtaining information related to a received signal received by the positioning device, the information including at least one of a bias estimate value and a gain control parameter based on the received signal; determining whether the potential fault in the positioning device is detected based on the information and a detection threshold, wherein: the gain control parameter includes a current gain of a programmable gain amplifier (PGA) in a receiver of the positioning device; the detection threshold includes a gain threshold that includes a nominal gain of the PGA plus an incremental value of gain; and determining whether the potential fault is detected includes: comparing the gain control parameter with the gain threshold; and in response to a comparison result that the gain control parameter is greater than the gain threshold, determining that the potential fault is detected.

2. The apparatus of claim 1, wherein, the nominal gain includes at least one of: a predetermined gain value stored in the at least one memory; an initialization gain value obtained from an initialization of the receiver; and a low-pass filtered gain value.

3. The apparatus of claim 1, wherein: the information includes an inter-channel bias (ICB) estimate value between two channels of a positioning system; the detection threshold includes a first ICB threshold and a second ICB threshold, wherein the first ICB threshold is greater than the second ICB threshold; and determining whether the potential fault is detected includes: at least one of: comparing the ICB estimate value with the first ICB threshold; and comparing the ICB estimate value with the second ICB threshold; and in response to one of: a comparison result that the ICB estimate value is greater than the first ICB threshold; and a comparison result that the ICB estimate value is less than the second ICB threshold, determining that the potential fault is detected.

4. The apparatus of claim 3, wherein: the ICB estimate value includes a current ICB estimate value; the first ICB threshold includes a nominal ICB estimate value plus a first incremental value of ICB; and the second ICB threshold includes a nominal ICB estimate value minus a second incremental value of ICB. the nominal ICB estimate value includes at least one of:

5. The apparatus of claim 4, wherein, a predetermined ICB value stored in the at least one memory; an initialization ICB value obtained from an initialization of a receiver of the positioning device; and a low-pass filtered ICB value. the ICB estimate value includes an estimate value of a group delay between the two channels of the positioning system.

7. The apparatus of claim 1, wherein:

6. The apparatus of claim 3, wherein, the received signal is a first received signal from a first positioning system; the positioning device is configured to receive a second received signal from a second positioning system; ​ ​ The information includes an inter-system bias (ISB) estimate between the first positioning system and the second positioning system based on the first received signal and the second received signal; The detection threshold includes a first ISB threshold and a second ISB threshold, wherein the first ISB threshold is greater than the second ISB threshold; and Determining whether the potential fault is detected includes: At least one of: comparing the ISB estimate to the first ISB threshold; and comparing the ISB estimate to the second ISB threshold; and Determining that the potential fault is detected in response to one of: a comparison result that the ISB estimate is greater than the first ISB threshold; and a comparison result that the ISB estimate is less than the second ISB threshold.

8. The apparatus of claim 7, wherein: The ISB estimate includes a current ISB estimate; The first ISB threshold includes a nominal ISB estimate plus a first delta value of ISB; and The second ISB threshold includes the nominal ISB estimate minus a second delta value of ISB. The nominal ISB estimate includes at least one of:

9. The apparatus of claim 8, wherein, a predetermined ISB value stored in the at least one memory; an initialization ISB value obtained from initialization of a receiver of the positioning device; and a low-pass filtered ISB value.

10. The apparatus of claim 1, wherein: The received signal is a first received signal from a first positioning system; The positioning device is configured to receive a plurality of received signals from a plurality of positioning systems including the first positioning system, the received signals including the first received signal; The information includes a multi-global navigation satellite system (GNSS) ISB estimate, i.e., a multi-GNSS ISB estimate, including a plurality of inter-system bias (ISB) estimates corresponding to a plurality of positioning system pairs; The detection threshold includes: a first multi-GNSS ISB threshold including a plurality of first ISB thresholds corresponding to the plurality of positioning system pairs; a second multi-GNSS ISB threshold including a plurality of second ISB thresholds corresponding to the plurality of positioning system pairs; a first system number threshold; and a second system number threshold, wherein the plurality of first ISB thresholds are respectively greater than the plurality of second ISB thresholds; and Determining whether the potential fault is detected includes: At least one of: comparing the plurality of inter-system bias (ISB) estimates to the plurality of first ISB thresholds, respectively; and determining that the multi-GNSS ISB estimate is greater than the first multi-GNSS ISB threshold when a comparison result that the plurality of inter-system bias (ISB) estimates are greater than the plurality of first ISB thresholds is greater than or equal to the first system number threshold; and ​ ​ comparing the plurality of inter-system bias (ISB) estimates to the plurality of second ISB thresholds, respectively; and determining that the plurality of GNSS ISB estimates is less than the second plurality of GNSS ISB thresholds when a comparison result is that a number of the plurality of inter-system bias (ISB) estimates is less than the plurality of second ISB thresholds is greater than or equal to the second system number threshold; and determining that the potential fault is detected in response to at least one of: determining that the plurality of GNSS ISB estimates is greater than the first plurality of GNSS ISB thresholds; and determining that the plurality of GNSS ISB estimates is less than the second plurality of GNSS ISB thresholds.

11. The apparatus of claim 1, wherein: the information comprises an inter-band bias (IBB) estimate between two bands of the positioning system; the detection threshold comprises a first IBB threshold and a second IBB threshold, wherein the first IBB threshold is greater than the second IBB threshold; and determining whether the potential fault is detected comprises: at least one of: comparing the IBB estimate to the first IBB threshold; and comparing the IBB estimate to the second IBB threshold; and determining that the potential fault is detected in response to one of: a comparison result that the IBB estimate is greater than the first IBB threshold; and a comparison result that the IBB estimate is less than the second IBB threshold.

12. The apparatus of claim 11, wherein: the IBB estimate comprises a current IBB estimate; the first IBB threshold comprises a nominal IBB estimate plus a first delta value of IBB; and the second IBB threshold comprises a nominal IBB estimate minus a second delta value of IBB.

13. The apparatus of claim 12, wherein, the nominal IBB estimate comprises at least one of: a predetermined IBB value stored in the at least one memory; an initialization IBB value obtained from an initialization of a receiver of the positioning device; and a low-pass filtered IBB value.

14. The apparatus of claim 11, wherein: the IBB estimate comprises a plurality of IBB band estimates corresponding to a plurality of band pairs; the first IBB threshold comprises a plurality of first IBB band thresholds corresponding to the plurality of band pairs; the second IBB threshold comprises a plurality of second IBB band thresholds corresponding to the plurality of band pairs; comparing the IBB estimate to the first IBB threshold comprises: comparing the plurality of IBB band estimates to the plurality of first IBB band thresholds, respectively; and determining that the IBB estimate is greater than the first IBB threshold when a comparison result is that a number of the IBB band estimates is greater than the first IBB band threshold is greater than a first band number threshold; and comparing the IBB estimate to the second IBB threshold comprises: comparing the IBB band estimates to the plurality of second IBB band thresholds, respectively; and determining that the IBB estimate is less than the second IBB threshold when a comparison result is that a number of the IBB band estimates being less than the second IBB band threshold is greater than a second band number threshold.

15. The apparatus of claim 1, wherein: the information comprises a gain control parameter and an offset estimate; the detection threshold comprises a gain threshold, a first offset threshold, and a second offset threshold, wherein the first offset threshold is greater than the second offset threshold; and determining whether the potential fault is detected comprises: comparing the gain control parameter to the gain threshold; at least one of: comparing the offset estimate to the first offset threshold; and comparing the offset estimate to the second offset threshold; and determining that the potential fault is detected in response to: a comparison result that the gain control parameter is greater than the gain threshold; and one of: (i) a comparison result that the offset estimate is greater than the first offset threshold; and (ii) a comparison result that the offset estimate is less than the second offset threshold.

16. The apparatus of claim 1, wherein, the information comprises an estimate of at least one of: an input spectrum of the positioning device; and a resulting pseudorange measurement residual for a given estimated position, the resulting pseudorange measurement residual having an estimated offset imposed based on the received signal.

17. A method for detecting a potential fault in a positioning device, the method comprising the steps of: obtaining information related to a received signal received by the positioning device, the information comprising at least one of a gain control parameter and an offset estimate based on the received signal in the positioning device; determining, based on the information and a detection threshold, whether the potential fault in the positioning device is detected; and in response to determining that the potential fault is detected, generating an indication that the potential fault is detected, wherein: the gain control parameter comprises a current gain of a programmable gain amplifier (PGA) in a receiver of the positioning device; the detection threshold comprises a gain threshold, the gain threshold comprising a nominal gain of the PGA plus an incremental value of gain; and determining whether the potential fault is detected comprises: comparing the gain control parameter to the gain threshold; and in response to a comparison result that the gain control parameter is greater than the gain threshold, determining that the potential fault is detected. the nominal gain comprises at least one of:

18. The method of claim 17, wherein, a predetermined gain value stored in at least one memory; an initialization gain value obtained from an initialization of the receiver; and a low-pass filtered gain value.

19. A non-transitory computer-readable medium for storing instructions that, when executed, cause a controller to perform operations for detecting a potential fault in a positioning device, the operations comprising: obtaining information related to a received signal received by the positioning device, the information comprising at least one of a gain control parameter and an offset estimate based on the received signal; ​ based on the information and a detection threshold, determining whether the potential fault in the positioning device is detected; and in response to determining that the potential fault is detected, generating an indication that the potential fault is detected, wherein: the gain control parameter comprises a current gain of a programmable gain amplifier (PGA) in a receiver of the positioning device; the detection threshold comprises a gain threshold comprising a nominal gain of the PGA plus an incremental value of gain; and determining whether the potential fault is detected comprises: comparing the gain control parameter to the gain threshold; and in response to a comparison result that the gain control parameter is greater than the gain threshold, determining that the potential fault is detected.

20. The non-transitory computer-readable medium of claim 19, wherein, the nominal gain comprises at least one of: a predetermined gain value stored in at least one memory; an initialization gain value obtained from an initialization of the receiver; and a low-pass filtered gain value.

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