Quantum spectrum sensing-assisted navigation

Abstract

In a general aspect, a quantum spectrum sensing-assisted navigation system is presented. In some implementations, a quantum spectrum sensing (QSS)-assisted navigation system includes a vapor cell sensor and a control system communicably connected to the vapor cell sensor. A method of operating the QSS-assisted navigation system on a mobile platform includes obtaining geolocation information associated with the mobile platform by operating a location detection system of the control system; obtaining output optical signals from the vapor cell sensor, the output optical signals being generated based on an interaction between the vapor cell sensor and electromagnetic signals present in an environment of the mobile platform; processing the output optical signals to determine characteristics of the RF signals; identifying the presence of navigation interference signals in the environment; and based on the identified navigation interference signals and the geolocation information, determining a navigation boundary for the mobile platform.

Description

Quantum Spectrum Sensing-Assisted NavigationCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 727,332, filed Dec 3, 2024, entitled "Using Quantum Spectrum Sensing Systems to Produce Navigation Data." The above-referenced priority document is incorporated herein by reference.TECHNICAL FIELD

[0002] The following description relates to quantum spectrum sensing (QSS)-assisted navigation.BACKGROUND

[0003] Navigation systems use navigation signals from various sources to determine a receiver’s position, velocity, or orientation. Such signals may include satellite-based signals from global navigation satellite systems (GNSS) such as GPS, Galileo, GLONASS, or BeiDou, as well as terrestrial, optical, acoustic, or inertial signals derived from communication networks, environmental features, or onboard sensors. By analyzing timing, phase, or signal strength parameters of these navigation signals, a receiver can calculate its location relative to known references. These systems are widely used in personal, transportation, autonomous, and defense applications.BRIEF DESCRIPTION OF THE DRAWINGS

[0004] FIG. 1 is a block diagram showing aspects of an example QSS-assisted navigation system.

[0005] FIG. 2 is a schematic diagram showing an example of a mobile platform guided by QSS-assisted navigation.

[0006] FIG. 3 is a flow chart showing aspects of an example QSS-assisted navigation process.DETAILED DESCRIPTION

[0007] In a general aspect, quantum spectrum sensing (QSS) -assisted navigation is used to identify electromagnetic radiation, such as navigation interference signals, that may affect navigation signals in an environment. In some examples, a QSS-assisted navigation system includes one or more vapor cell sensors and a control system operatively coupled to the one or more vapor cell sensors. The vapor cell sensors are configured to interact with incident electromagnetic radiation, and the control system is configured to process data from the vapor cell sensors, characterize detected signals, and determine whether navigation interference signals are present. QSS-assisted navigation may be deployed in connection with a variety of mobile platforms. For example, a QSS-assisted navigation system may be installed (e.g., mounted) on manned or unmanned aerial, terrestrial (land or sea), or space vehicles, and on associated ground control stations.

[0008] In some environments, navigation signals include positioning, navigation, and timing (PNT) signals, such as GNSS (Global Navigation Satellite System) signals (e.g., GPS, Galileo, GLONASS, BeiDou) and related satellite-based signals, which may be transmitted in bands such as LI, L2, and L5 and, in some implementations, in portions of S, X, Ku, Ka, or higher bands including LEO-enhanced GNSS systems above about 40 GHz. Navigation signals can further include non-satellite sources such as terrestrial communication or ranging signals (e.g., cellular, Wi-Fi, Bluetooth, ultra-wideband) and environmental reference signals (e.g., magnetic, optical, acoustic, radar, or lidar features), which may be combined with data from onboard inertial sensors (e.g., accelerometers, gyroscopes, barometers, and odometers). A location detection system may fuse information from one or more of these sources to maintain navigation when GNSS signals are degraded, obstructed, or unavailable.

[0009] In some environments, navigation interference signals may include any electromagnetic, acoustic, or optical signal, intentional or unintentional, that disrupts, distorts, attenuates, or otherwise degrades reception or processing of navigation signals used by a mobile platform. Such interference can include jamming or spoofing transmissions, multipath reflections, signal absorption, or emissions from nearbyelectronic equipment that reduce signal-to-noise ratio, corrupt timing information, or distort ranging measurements. Detection and characterization of navigation interference signals can be used to identify interference-affected regions, to define boundaries between interference-free and interference-affected regions, and to adapt navigation processing when a mobile platform transitions between such regions.

[0010] In some implementations, QSS-assisted navigation systems employ Rydberg- atom-based vapor cell sensors as spectrum sensors. Rydberg-atom-based vapor cells can be configured as substantially omni-directional, self-calibrating sensing elements with wide carrier bandwidth, enabling detection of signals over ultra-broadband spectra (for example, approximately 0.10-100 GHz) without changing sensing elements. The vapor cells can be implemented without active RF electronics, such as low-noise amplifiers, thereby enabling passive operation that does not introduce significant additional RF frequency components. The vapor cell sensors can be hardened or ruggedized for outdoor and field conditions, including temperature, humidity, shock, and vibration, and can be used for spectrum sensing in bands employed by navigation systems, wireless infrastructure, and base stations, including 5G and 6G deployments.

[0011] In some implementations, the systems and techniques described herein provide improved (e.g., more resilient, reliable or accurate) navigation systems for manned and unmanned aerial, terrestrial, and space vehicles by enabling detection and characterization of navigation interference signals across satellite and non-satellite navigation bands. By leveraging passive, ultra-broadband spectrum sensing, QSS-assisted navigation systems can support more robust maintenance of position, velocity, attitude, and timing information in the presence of jamming, spoofing, multipath, and other interference sources, and can support fail-over or redundancy strategies across multiple constellations, frequency bands, and auxiliary navigation sources.

[0012] In some implementations, a QSS-assisted navigation system provides advantages including ultra-broad carrier bandwidth using a single sensor, tolerance to high-power RF signals, passive and low-observability operation due to electromagnetic transparency, rapid wideband scanning suitable for real-time spectrum analysis, and size, weight, power, and cost (SWaP-C) characteristics compatible with mobile platforms. These characteristicscan make QSS-assisted navigation systems well-suited for navigation applications in interference-affected regions and for spectrum survey applications (e.g., 5G / 6G site surveys), while reducing the need for multiple band-specific antennas or front-ends used in conventional systems.

[0013] FIG. 1 is a bock diagram showing aspects of an example QSS-assisted navigation system 100. The example QSS-assisted navigation system 100 includes a vapor cell sensor 102 and a control system 104 communicably connected to the vapor cell sensor 102. As shown in FIG. 1, the vapor cell sensor 102 is coupled to the control system 104 via a transmission medium 106, e.g., optical fibers or other optical communication links. In some instances, the QSS-assisted navigation system 100 includes other components and features. In some cases, the example QSS-assisted navigation system 100 may operate in the environment shown in FIG. 2 or in another type of navigation environment. In some cases, the example QSS-assisted navigation system 100 may operate according to the example process 300 shown in FIG. 3, or the example QSS-assisted navigation system 100 may operate in another manner.

[0014] In some implementations, the QSS-assisted navigation system 100 includes a mounting system and power supply. In some instances, the QSS-assisted navigation system 100 can be carried on a mobile platform (e.g., unmanned and manned aerial, terrestrial and space vehicles). In some instances, the QSS-assisted navigation system 100 is configured to detect electromagnetic signals in an environment of the mobile platform, determine whether navigation interference signals are present in the environment, and identify interference-free regions and interference-affected regions. In some instances, the QSS- assisted navigation system 100 can be used to create an interference map which can be used to guide its own navigation operations or shared with an external monitoring system or other mobile platforms to guide their navigation operations. In some instances, the QSS- assisted navigation system can be used for other purposes.

[0015] In some implementations, the QSS-assisted navigation system 100 is configured to provide absolute, self-calibrated measurements over an ultra-broadband carrier bandwidth (e.g., 1 to 100 GHz, or another radio frequency (RF) frequency range) as a spectrum analyzer. For instance, these and potentially other capabilities may be providedby using a non-perturbative, all dielectric vapor cell sensors. The example control system 104 is compact, portable, lightweight; and thus, can be carried in a portable storage bag (e.g., backpack) or another type of portable platform. For example, the QSS-assisted navigation system 100 can be carried by a mobile platform and used for characterizing emissions from communication nodes in a wireless communication network, e.g., a node B, an E-utran Node B (also known as Evolved Node B, eNodeB or eNB), a pico station, a femto station, or another type of communication node. The ultra-broadband nature of the QSS- assisted navigation system 100 can be used for characterizing or conformance-testing of 5G-6G base station transmitters in the field by determining properties of the wireless signals transmitted in a wireless network environment, and characterizing emissions from wireless communication infrastructures (e.g., satellite communication systems, radar systems, microwave links, etc.) in an electronic warfare environment. In some instances, the QSS-assisted navigation system 100 may be used for determining properties of wireless signals in another environment.

[0016] As shown in FIG. 1, the vapor cell sensor 102 can be implemented as a Rydberg atom-based vapor cell sensor. In some instances, the vapor cell sensor 102 includes a vapor in an enclosed volume (e.g., in a vapor cell). The vapor is used as a medium to interact with electromagnetic radiation (e.g., the wireless signals). In some implementations, the vapor cell sensor 102 utilizes the quantum states of Rydberg atoms for absolute measurement of electromagnetic radiation. In some instances, the vapor cell sensor 102 may be implemented as a metrology vapor cell, a glass vapor cell, a microelectromechanical system (MEMS) vapor cell, or another type of engineered vapor cell based on metamaterial or photonic crystal principles.

[0017] In some implementations, the vapor cell sensor 102 can provide a number of advantages, in various contexts. For instance, Rydberg-atom-based vapor cells are not typically damaged by large RF signals, such as electromagnetic pulses or other types of high-power jamming signals in electronic warfare or radar pulses, when using the device to calibrate RF equipment in the field. Therefore, it can provide a unique jamming-resistance and resilience for these use cases. Rydberg-atom-based vapor cells may be implemented without active electronics, such as a low-noise amplifier (LNA), which enables passivesensing. Accordingly, Rydberg-atom-based vapor cells may operate without generating any additional RF frequency signal components (in particular under nonlinearity). Therefore, a QSS-assisted navigation system may provide a non-detectable, spectrum sensing system of interest to electronic warfare spectrum sensing use cases. In some instances, a Rydberg- atom-based vapor cell sensor of QSS-assisted navigation system can be hardened and ruggedized for outdoor, field portability and environmental conditions, including temperature, humidity, shock, vibration. In some instances, a QSS-assisted navigation system can significantly improve time and efficiency of site surveys for wireless infrastructure and base stations, including 5G and 6G. Site surveys for 5G-6G base stations may focus on both microwave (FR1, <7.125 GHz) and millimeter-wave (FR2, >24.250 GHz) bands of the electromagnetic spectrum. Signal identification may include all signals present in an ultra-broadband bandwidth (0.1-100 GHz, as an example).

[0018] In some aspects of operation, RF radiation or other electromagnetic radiation is received by the vapor cell sensor 102, and the RF radiation passes through an exterior (e.g., formed of the dielectric material) of the vapor cell sensor 102 to interact with the vapor residing in the vapor cell sensor 102. During such interaction, input optical signals from the control system 104 can be communicated to the vapor cell sensor 102. The input optical signals pass through atoms in the vapor, which undergo a change in optical transmission due to the presence of the electromagnetic radiation; and output optical signals can be generated based on the interaction between the input optical signals, the vapor and the electromagnetic radiation. In some implementations, the generated output optical signals from the vapor cell sensor 102 are used to determine properties of the wireless signals. In some implementations, the properties of the wireless signals can be used to determine the power of the wireless signal emitted from the cellular base station, to determine the location of the sources of the wireless signals, or for other purposes.

[0019] In some instances, when used in the field, the vapor cell of the vapor cell sensor 102 can be hermetically sealed and packaged in an electromagnetically transparent dielectric material, such as polylactic acid (PLA) plastic materials and other dielectric materials. The vapor cell can be mast mounted (e.g., on a telescopic mast or another type of mast) or fixed to another type of support structure, like a tripod, for supporting the vaporcell and its associated optical components (e.g., waveguides, optical connectors, etc.) at their respective locations. In some instances, when the QSS-assisted navigation system 100 includes multiple vapor cell sensors 102, the multiple vapor cell sensors 102 may be configured in an array and oriented in the same or different directions. In this case, the array of vapor cell sensors may be supported by a support structure at their respective locations in the array. In some instances, the multiple vapor cell sensors may be configured in the two-dimensional array or in any other one-dimensional, two-dimensional, or three- dimensional arrays. The multiple vapor cell sensors in the array can be communicably connected to the shared control system 104 through an array of optical channels that connect the array with the portable control system. Arrays of vapor cell sensors 102 can be used to sense different RF frequencies. Arrays can also be configured to determine the angle of arrival which can be used to determine the direction of the signal received and to differentiate signals from satellites or jammers. Collection and focusing elements such as lenses can be used in some cases. The vapor cell sensors 102 can be passive sensors. These arrays can be reconfigured by the user.

[0020] In some implementations, the vapor cell sensor 102 is formed at least in part (wholly or partially formed) of a dielectric material that is transparent to the electromagnetic radiation. The vapor cell sensor 102 may be of the type described, for example, in the publications "Microwave electrometry with Rydberg atoms in a vapor cell using bright atomic resonances," by J. A. Sedlacek, et al. Nature Physics 8, 819-824, 2012) and "Three-photon Rydberg-atom-based radio-frequency sensing scheme with narrow linewidth," by Bohaichuk et al. (Phys. Rev. Appl. 20, L061004, 2023). Other types or configurations of a vapor cell sensor 102 may be used in some cases. The dielectric material may define a window for the vapor cell sensor 102, through which the electromagnetic radiation is received. Examples of the dielectric material include silicon, silicate-based glasses, and quartz. The vapor cell sensor 102 may include Rydberg atoms or Rydberg molecules in a vapor state (e.g., vaporized87Rb or133Cs) that alter an optical transmission in response to the electromagnetic radiation. The optical transmission may be influenced by optical transitions of the atoms or molecules in the vapor state. For example, electromagnetic signals may interact with a vapor having Rydberg states (e.g., a vapor ofRydberg atoms (e.g., Rb, Cs, etc.), Rydberg molecules (e.g., H2, 12, etc.) or possibly both), thus altering the vapor’s optical transmission properties and the output optical signals. In some instances, the output optical signal from the vapor cell sensor 102 can be generated based on electromagnetically induced transparency (EIT) or electromagnetically induced absorption (EIA). In some instances, a sub-Doppler method is useful for higher spectral resolution in the Autler-Townes regime and higher sensitivity.

[0021] In some instances, the generated output optical signals are independent of an orientation of the dielectric cell relative to the source of the electromagnetic emission. For example, the vapor cell sensor 102 may be rotated without impacting the output optical signals generated by the vapor cell sensor 102. In other words, the vapor cell sensor 102 can be omni-directional such that its operation is invariant under spatial rotations, providing a higher degree of stability. In some instances, the vapor cell sensors of the QSS- assisted navigation system can be small sensors designed for electromagnetic transparency, for example, MEMs-based vapor cells, glass vapor cells, glass and silicon vapor cells, or other types of vapor cell sensors, for example, as described in U.S Patent Nos. 11,300,599, 11,307,233, 11,899,057, 11,391,797, 11,313,926, 11,366,430, 10,859,981, and 10,605,840.

[0022] In some implementations, the control system 104 is configured to generate / communicate input optical signals to the vapor cell sensor 102; and to receive / process output optical signals from the vapor cell sensor 102. As shown in FIG.l, the control system 104 includes a laser system 112, a photonic integrated circuit system 114, a system-on-chip 116, a power supply 118, an interface 120, a location detection system 122, and a clock 126. In some instances, the control system 104 may include other components.

[0023] In some implementations, the laser system 112 includes two or more lasers configured to generate two or more direct laser output signals. For example, the laser system 112 includes a probe laser configured to generate a direct probe laser, and one or more coupling lasers configured to generate one or more direct coupling lasers. In some instances, the laser system 112 of the QSS-assisted navigation system 100 may include semiconductor lasers for reduced SWaP-C. In some instances, the laser system 112 mayinclude RF optics such as a lens or parabolic dish to increase the sensitivity. In some instances, each of the two or more lasers may be a fiber laser, a distributed feedback (DFB) laser, or a Bragg reflector (DBR) laser. In some instances, each of the two or more lasers of the laser system 112 may be a continuous wave (CW) laser, a narrow-linewidth tunable laser, for example, using external cavity diode laser (ECDL) technology, or other types of lasers. Gain chips coupled with the photonic integrated circuit (PIC) system 114 for feedback are also a possibility. It is also possible to combine the PIC system 114 such that laser stabilization and modulation are possible on the same device. A heterogenous PIC system 114 is also possible, where lasers, modulators, laser stabilization, line narrowing and routing are combined on the same chip. In some instances, the two or more laser signals generated by the laser system 112 are locked to a stable, narrow bandwidth reference such as a frequency comb signal, interferometer, atomic or molecular absorption line, or another type of reference. In some instances, each of the lasers of the laser system 112 may be connected to a corresponding frequency reference (e.g., absolute or approximately absolute) or a laser stabilizer configured to lock the frequency of the direct laser output signal from the laser. For example, an absolute reference may be an interferometer (e.g., a Fabry-Perot cavity) or a molecular or atomic spectral feature. In some instances, the laser system 112 may include multiple agile laser system (e.g., two or more coupling laser systems), for example, at different frequencies to provide closed loop systems for reading out phase optically. In some instances, other multi-photon detection schemes may be possible. In some examples, the cavities can be waveguide cavities such as PIC devices such as Bragg reflectors or ring resonators (or series of ring resonators) that can ensure single frequency and single mode operation.

[0024] In some instances, the probe laser of the laser system 112 can provide ~150 mW of power with a linewidth of —1-10 kHz. In some instances, a probe laser beam output from the probe laser may have another power with another linewidth. The probe laser does not have to be widely tunable. Narrow bandwidth semiconductor lasers may be ECDLs or gain chips self-injection locked with PICs to get very narrow linewidths and stability (low bandwidth feedback loops). Other types of lasers such as fiber lasers, VCSELS and MEXSELs are also possible. In some implementations, the probe laser can be fiber coupled with in-housing isolators. In some instances, the coupling laser, or lasers, may be operated at 509 nm or 2.2 pm. When the coupling laser operates at 2.2 pm, a narrow bandwidth 636 nm coupling laser beam with a reasonable power, e.g., ~100 mW delivered to the vapor cell may be used. The 636 nm laser acts as second coupling laser. These wavelengths are appropriate examples for the Cs atom. Other wavelengths are possible as are other atoms, e.g., Rb, which may require other wavelengths.

[0025] In some instances, each coupling laser of the laser system 112 can provide > 2W of power with a linewidth of —1-10 kHz if it is monolithic. The coupling laser can be widely tunable, —5-10 nm. When the coupling laser is amplified using a fiber or semiconductor laser (e.g., tapered amplifier, semiconductor optical amplifier, fiber amplifier, etc.), the power to seed the amplifier can be provided, for example, usually > 20 mW, by another stable laser such as a semiconductor laser or a fiber laser. When a coupling laser comb is used, the coupling laser may be provided with enough power to accommodate a loss in the comb and switch components to seed an amplifier whose output power is targeted to a particular application, usually > 150 mW. Examples of comb generators are described in Dixon, et al., "Rydberg-Atom-Based Electrometry Using a Self-Heterodyne Frequency-Comb Readout and Preparation Scheme," Physical Review Applied 19, 034078 (2023); and Liu, et al., "Stable, narrow-linewidth laser system with a broad frequency tunability and a fastswitching time," Optics Letters 49, 399 (2024), U.S. Patent No. 11,658,461, and U.S. Patent No. 11,874,311. Other types of comb generators may be used in some cases. The coupling laser beam generated by the coupling laser can be amplified by fiber or semiconductor amplifiers as it passes through comb and switching systems. In some instances, the coupling laser may provide a coupling laser beam with a power of another value with a linewidth of another value.

[0026] In some implementations, the photonic integrated circuit system 114 is configured to receive the direct laser output signals (e.g., probe and coupling laser beams) from the laser system 112 and process the direct laser output signals to generate the input optical signal to the vapor cell sensor 102. In some instances, the photonic integrated circuit system 114 may include one or more chips, each of which includes multiple photonic components integrated together. In some instances, the photonic integratedcircuit system 114 is configured to perform functions related to the generation, manipulation, and detection of light on a compact chip. In some instances, the photonic integrated circuit system 114 can enable the miniaturization of optical systems by integrating multiple photonic functions on a single chip; can reduce size, weight, and power consumption. In some instances, the photonic integrated circuit system 114 can operate at very high data rates and less signal loss. The photonic integrated circuit system 114 can be scalable and cost-effective for mass production. In some instances, the photonic integrated circuit system 114 can be based on various material platforms, including silicon, indium phosphide, silicon nitride, and other material platforms.

[0027] In some implementations, the photonic integrated circuit system 114 includes a first comb generator configured to receive a direct probe laser beam from a probe laser and generate a first frequency comb signal; and a second comb generator configured to receive a direct coupling laser beam and generate a second frequency comb signal. Each of the first and second frequency comb signals is an optical signal produced by the first or second comb generators; and each of the first and second frequency comb signals has a combshaped frequency profile that is defined by comb lines at respective comb frequencies. In some implementations, each of the first and second comb generators includes a photonic integrated circuit made of thin film lithium niobate for electro-optic comb generation. In some instances, each of the first and second comb generators may be based on an electrooptic modulator, a mode-locked laser, an optical micro-resonator, a nonlinear optical fiber, an acousto-optic modulator, or another type of comb generator. In some instances, when the QSS-assisted navigation system 100 includes multiple vapor cell sensors 102, the multiple vapor cell sensors can be configured to receive respective frequency components of the second frequency comb signal. In other words, each vapor cell sensor can be configured to receive one or more respective frequency components of the second frequency comb signal. In some instances, the multiple vapor cell sensors operating at multiple frequencies can provide micro-diversity information in the field.

[0028] In some instances, the first frequency comb signal may be a probe laser comb signal which can be created using electro-optic modulation. For example, the probe laser comb signal may be generated by waveguide electro-optic modulators, on-chip PICmodulators, or by another technology. In some instances, PIC modulators can be constructed using, for example, TFLN on silicon to form waveguides that can be electrically modulated. In certain examples, the modulators can create a comb with tooth spacings of kHz-MHz depending on the desired spectral resolution with breadths of up to 1 GHz. Typically, the waveguide electro-optic modulators are made from lithium niobite or potassium titanyl phosphate (KTP).

[0029] In some implementations, the second frequency comb signal may be a coupling laser comb signal which is used so that the coupling laser beam can remain locked to a fixed frequency reference yet generate light for all possible or desired Rydberg transitions. The coupling laser comb signal may span a range of wavelengths, for example, ~5-10 nm or another range. The coupling laser comb signal can be constructed so that the comb tooth spacing is ~10-30 GHz. The coupling laser comb signal may include ~30-90 comb teeth or a different number of teeth. The electro-optics can be either waveguide electro-optics, made from lithium niobite or potassium titanyl phosphate (KTP), or on-chip thin film electrooptics, typically made with lithium niobite on silicon. Other materials such as Tantalum Pentoxide may also be possible to use. The coupling laser comb signal may be generated using electro-optic modulators similar to those for the probe laser comb signal. In some examples, the generation of the coupling laser comb signal may utilize 3-5 of the electrooptic modulators. PIC electro-optic modulators could be substantially smaller because the Tt-phase voltage is expected to be smaller.

[0030] In some implementations, the photonic integrated circuit system 114 includes one or more optical amplifiers configured to receive and amplify the direct laser output signals prior to being processed by the respective comb generators. For example, the photonic integrated circuit system 114 includes an optical amplifier to receive the direct probe laser; and the amplified probe laser output signal can then be received and processed by the first comb generator. The photonic integrated circuit system 114 includes an optical amplifier to receive the direct coupling laser; and the amplified coupling laser output signal can then be received and processed by the second comb generator. In some instances, the multiple optical amplifiers may be configured and connected in another manner in the photonic integrated circuit system 114.

[0031] In some implementations, the optical amplifiers of the photonic integrated circuit system 114 are semiconductor amplifiers, namely tapered amplifiers or semiconductor amplifiers. In some instances, the optical amplifiers may include fiber optic amplifiers, tapered amplifiers, or other types of amplifiers. The amplifiers for the probe and coupling laser output are high power amplifiers that can output > 150 mW of power. Intermediate stage, so called 'booster amplifiers’, can output less power. The booster amplifiers can be configured to boost the power levels of the probe and coupling laser beams in order to compensate for loss in the comb and switching systems. The laser outputs of the comb and switching laser systems can be large enough to seed the high- power amplifier placed at the output of the system. If the output of the comb and switching laser system is > 50 mW the high-power amplifier may not be required for some applications. In some instances, the semiconductor amplifiers may have the same size as the probe and coupling lasers. In some examples, when the amplifier includes a tapered amplifier, the amplifier includes a heat sinking device. In some instances, a semiconductor amplifier (high power) can be operated at either 2.2 micrometers (pm), 1018 nanometers (nm), or 509 nm. Higher output power is required when several, or many, vapor cell sensors 102 are operated in the QSS-assisted navigation system 100. To alleviate power requirements, it may be possible to faster scan the one or more coupling lasers, the probe laser, or both, through the vapor cell sensors 102. The raster can be done throughout the array of vapor cell sensors or can be done through one or more subsets of the vapor cell sensors.

[0032] In some implementations, the photonic integrated circuit system 114 includes a frequency separator which is configured to receive the second frequency comb signal and select one or more frequency components from the second frequency comb signal. In some instances, the photonic integrated circuit system 114 may include a switch / filter module including a switch network and a network of drop-out filters. In some instances, the switch network may be configured to select one or more frequency components in the second frequency comb signal. In some instances, the switch network includes an electro-optic switching network. In some instances, the network of drop-out filters can be tuned near each frequency component of the second frequency comb signal. In this case, the outputs ofthe drop-out filters maybe combined, in whole or in part. In some instances, the drop-out filters can be tuned by using micro-heaters or piezoelectric elements.

[0033] In some implementations, the photonic integrated circuit system 114 includes a frequency fine-tuning module. The frequency fine-tuning module may include one or more fine-tuning elements each configured to apply a frequency shift to one or more frequency components of the second frequency comb signal. The input optical signal to the vapor cell sensor 102 may include one or more shifted frequency components from the second frequency comb signal. In these implementations, the switching speed of the coupling laser system may be determined by the switches used and the frequency relock time of a radio frequency oscillator driving the frequency fine-tuning module.

[0034] In some implementations, fine-tuning elements of the photonic integrated circuit system 114 includes a specialized electro-optic modulator, configured as a Mach-Zehnder interferometer, a so called "IQ" modulator. In some implementations, an IQ modulator enables the fine-tuning element to use single side band suppressed carrier modulation to shift the optical frequency from the switch and filter to the Rydberg state that is desired. The fine-tuning element works over the comb tooth separation to tune light generated from the comb across the spectrum continuously. The electro-optic modulator can be a modified version of the ones used for the comb generation. In some instances, the bandwidth of the fine-tuning elements may at least match the comb tooth separation of the coupling laser comb. Multiple fine-tuning elements can be used to sense multiple RF frequencies in the same and / or multiple vapor cells. Each output configured by the dispersive and switch system can implement a fine-tuning element. The fine-tuning elements can be implemented and then recombined into a single output channel to sense multiple frequencies, or can be routed to separate vapor cell sensors. Combinations of several vapor cells linked to different output channels can also be used. The recombination of the light output by the fine-tuning elements can be done using fiber combiners or a PIC circuit.

[0035] In some instances, the system-on-chip 116 includes one or more chips which consolidate various electronic components. For example, the system-on-chip 116 may include one or more processors, one or more memory units, and one or more input / output(I / O) ports. In some instances, the system-on-chip 116 may include one or more digital signal processors, wireless communication modules, and other components. The system- on-chip 116 can integrate numerous components into a single chip, reducing the overall size of the QSS-assisted navigation system 100 and the power consumption.

[0036] In some implementations, the system-on-chip 116 includes a radio frequency (RF) integrated circuit specifically designed to operate at radio frequencies (RF). In some instances, the RF integrated circuit of the system-on-chip 116 includes various components that are configured to perform functions such as generation, transmission, reception, and processing of RF signals. For example, the RF integrated circuit of the system-on-chip 116 may include amplifiers, oscillators, filters, modulators, switches, attenuators, optical detectors, transmission lines, and other devices and components for performing RF functions. In some instances, the system-on-chip 116 is configured to communicate control signals to devices and components of the laser system 112 to generate the two or more laser beams. In some instances, the system-on-chip 116 can be configured to communicate control signals to devices and components of the photonic integrated circuit system 114 to process the two or more laser beams to generate the input optical signals, which may be directed through the vapor in the vapor cell sensor 112 to probe and measure the response of the vapor to the received electromagnetic radiation. In some instances, the system-on- chip 116 may include respective controllers for respective components of the laser system 112 and the photonic integrated circuit system 114. For example, the system-on-chip 116 may include a comb controller, a switch controller, a fine-tuning controller, or other controllers for communicating control signals. For example, the system-on-chip 116 may include the respective controllers of sub-systems (e.g., the laser system 112, the photonic integrated circuit system 114, the communication module 124, the location detection system 122, etc.). In some instances, the controllers can interact with a master controller (typically a computer processor), where each functional element runs as a server. Each server delivers and receives information that is used by the user and autonomous control systems to run the system. In certain examples, FPGAs and GPUs, as well as other electronic systems, can be used to form a hybrid control system. It is also possible to segregate someor all of the control and signal processing functions on different boards to form the control system.

[0037] In some instances, switches and filters of the system-on-chip 116 can be built around electro-optics, micro-mechanical mirrors, Bragg gratings or PIC drop-out filters. In some examples, the PIC drop-out filters may include resonant ring resonators that can be tuned so that the desired frequency passes into the resonator and then is out coupled into a separate optical line. These ring resonators can be tuned electrically, thermally or piezoelectrically. An electro-optic element within the ring resonator is also possible to implement in order to tune the ring resonator. If the ring resonators are made with an electro-optic material, such as lithium niobite, they can be tuned electrically, through the electro-optic effect. These systems can act as a dispersive element and switch; therefore, they are efficient. Electro-optic switches can be made on a photonic integrated circuit so as to make the system compact. If an on-chip electro-optic switch tree is used, a dispersive element to separate the comb teeth may be used. In some instances, separation of the comb teeth can be accomplished by using an arrayed waveguide grating (AWG). The AWG is a waveguide device; can be fiber coupled. The electro-optic switch tree can be of similar size. In some instances, a PIC filter may have a size of one of the electrooptic on-chip modulators. A compact device can also be made by combining an AWG and a set of micromechanical mirrors. These devices can disperse light from a single optical channel and recombine it by changing the pointing angle of the micromechanical mirror to direct it to an output fiber. The switch tree can be configured to route light to a single, or multiple, output channels. A high degree of flexibility can be realized by changing the topology of the dispersive and switching systems. PIC circuits are ideal to fully implement the maximum flexibility of the overall system.

[0038] In some implementations, the system-on-chip 116 may be configured to detect the output optical signals from the vapor cell sensor 122, e.g., by operation of an optical detector. The optical detector senses changes in the transmission caused by the electromagnetic radiation at the vapor cell sensor 112. The system-on-chip 116 can convert an output electrical signal generated by the optical detector to digital data. In some implementations, the system-on-chip 116 includes a signal processing system configuredto process the output optical signals. The digitized output optical signal can be processed by operation of the signal processing system to determine properties of the electromagnetic radiation experienced by the vapor over the time period when the output optical signals were generated. In some implementations, the digitized output optical signal is transformed from the time domain to the frequency domain. In some instances, the transformation may include a wavelet transformation, a Fourier transformation, a Legendre transformation, a Hilbert transformation, Wigner transformation or other related transformations for frequency-domain analysis or time-frequency-domain analysis. In some instances, the system-on-chip 116 may process the digitized output optical signal to determine at least one of a start time, a duration, an amplitude, a frequency, a polarization, and other properties of the electromagnetic radiation experienced by the vapor during the time period. In some instances, determining the properties of the electromagnetic radiation may be performed locally at the QSS-assisted navigation system 100 or remotely at an external monitoring system 134. In some instances, the system-on-chip 116 may include other devices and components; and may be configured to perform other functions.

[0039] In some instances, a photodetector of the system-on-chip 116 can be a photomultiplier tube, an avalanche photodiode, a conventional photodiode, or other types of optical detectors. To perform a probe laser comb readout, the transmitted probe signal passing through the vapor cell is combined with a reference signal from the probe laser to generate beat signals between the comb teeth (e.g., comb frequencies) of the probe laser comb signal and reference. These beat signals represent the light that is transmitted at each comb frequency. Multiple comb frequencies (e.g., all comb teeth) can be measured at the same time by analyzing the spectrum using electronics, usually digital electronics as the photodetector signal is passed through an analog to digital converter to a digital signal processing system. The photodetector signal can be amplified using a low noise amplifier. The bandwidth of the photodetection system may match the comb bandwidth, up to ~ 1 GHz. Multiple photodetectors can be utilized by the system. Each vapor cell may require a photodetector.

[0040] In some instances, the system-on-chip 116 can include a hybrid FPGA, GPU, computer processor board such as a Xilinx Ultra-scale board, or other types of boards. Thesystem-on-chip 116 may have a board and a dedicated computer processor. The system- on-chip 116 are configured to perform signal processing and control other components of the example QSS-assisted navigation system 100, both automatically and in response to the user. The system-on-chip 116 can also host the user interface and pass user information to the user through a screen or interface, such as a LAN connection. The data can be communicated in part or can be communicated in whole to a remote node. The data communicated to the remote node can be RF spectral data, timing data, and geolocation data, or some combination of these. The data communicated to the QSS-assisted navigation system 100 can be information such as topographical corrects, signals data, and RF frequency ranges of interest, amongst other derived quantities.

[0041] As shown in FIG. 1, the system-on-chip 116 of the control system 104 includes a clock 126 for absolute timing. In certain examples, the clock 126 may be an atomic clock, a thermally stabilized crystal oscillator, a GPS steered atomic clock, a chip scale atomic clock, or another type of accurate stable clock. In some implementations, the clock 126 is configured to provide timing data associated with the output optical signals generated by the vapor cell sensor 102. In some instances, when the properties and characteristics of the electromagnetic radiation are determined locally at the QSS-assisted navigation system 100, the timing data and position data can be associated with the characteristics of the electromagnetic radiation.

[0042] In some instances, the control system 104 may include a memory unit configured to store data and computer-readable codes that can be executed. The computer- readable code may be modified or updated (e.g., based on user input or other information) to modify values of control parameters of the system-on-chip 116, values of processing parameters of the system-on-chip 116, or values of other parameters. For example, the digitized and transformed output optical signals associated with a vapor cell sensor 102 as a function of time can be stored in the memory unit. The interface 120 may also be used to run diagnostics to monitor the health of the QSS-assisted navigation system 100. In some instances, the control system 104 includes an autonomous system, which may interface with a user through the interface 120 or otherwise. In some instances, the autonomous system may be configured to automatically run in the background to perform functionssuch as maintaining the laser frequencies at fixed values, maintain laser power, apply signal processing, e.g., using matched filters, etc.

[0043] In some implementations, at least some of the optical components and subsystems of the QSS-assisted navigation system 100 can be connected via optical waveguide, e.g., fiber optics, or optical micro-bench technology. In some instances, at least some of the components of the example QSS-assisted navigation system 100 can be sealed and electrically connected with MIL-STD-810 connectors and headers.

[0044] In some instances, the interface 120 may provide communication with other QSS-assisted navigation systems or devices, or a central computer system or a data hub, or an external monitoring system. As shown in FIG. 1, the interface 120 includes a communication module 124 that can provide wireless communication under various wireless protocols, such as, for example, Bluetooth, Wi-Fi, Near Field Communication (NFC), GSM voice calls, SMS, EMS, or MMS messaging, wireless standards (e.g., CDMA, TDMA, PDC, WCDMA, CDMA2000, GPRS) among others. Such communication may occur, for example, through a radio-frequency transceiver or another type of component. In some implementations, the wireless communication module 124 is an optical communication module which includes optical transmitter and receivers for communicating optical signals over a transmission media (e.g., optical fibers). In some instances, the optical communication module can allow the QSS-assisted navigation system 100 to be optically connected to other QSS-assisted navigation system 100 or devices (e.g., the central computer system or the data hub). The communication module 124 allows the QSS-assisted navigation system 100 to exchange information with other QSS-assisted navigation system 100 or the external monitoring system 134 directly or through an intermediary entity (e.g., satellite, airplane, etc.) to facilitate the communication. In some cases, the interface 120 includes a wired communication interface (e.g., USB, Ethernet, etc.) that can be connected to one or more input / output devices, such as, for example, a keyboard, a pointing device, a scanner, or a networking device such as a switch or router, for example, through a network adapter.

[0045] In some implementations, the communication module 124 is configured to communicate with one or more other QSS-assisted navigation systems 100 on one or morewireless communication channels. For example, a communication module 124 may include a transceiver module including RF transmitter and receiver circuitry coupled to one or more antennas that can support a particular wireless communication protocol. In some instances, a central computer system includes a computer processor, a memory unit, and a communication module. In certain examples, a central computer system can include a QSS- assisted navigation system and additional computer systems. In some implementations, the central computer system is configured to receive respective navigation data from respective QSS-assisted navigation systems via respective wireless communication channels; and can perform further processing of the navigation data. The central computer system may be configured to determine the properties of the electromagnetic radiation; change configurations of the QSS-assisted navigation systems to perform different measurements (e.g., in a different frequency range, longer dwelling time, etc.); share the navigation data with other mobile platforms; and perform other functions.

[0046] In some instances, the location detection system 122 may be a Global Navigation Satellite System (GNSS) receiver configured to provide location information of the vapor cell sensor 112. For example, the location detection system 122 in the QSS-assisted navigation system 100 may be compatible with at least one of the following technologies, Global Positioning System (GPS), GLObal Navigation Satellite System (GLONASS), Galileo, or Beidou. Another type of geolocation device or system may be used to provide location information, in some cases. In some instances, the location detection system 122 is configured to determine the measurement location of the vapor cell sensor 112; and provide geolocation data associated with vapor cell sensor 112 from which the output optical signal is received.

[0047] In some implementations, low-earth orbit (LEO) and medium-earth orbit (MEO) satellites in a GNSS-based navigation system operate in frequency bands including LI band of 1575.42 MHz, L2 band of 1227.60 MHz, and L5 band of 1176.45 MHz. In some instances, the GNSS-based navigation system for PNT may operate in other frequency bands ranging across the S, X, Ku and Ka bands. In some instances, LEO-enhanced GNSS system could operate in a frequency range above 40 GHz. LEO orbits and higher transmitter powers will increase the GNSS signal level, while multiple constellations will diversify the signals.

[0048] In some implementations, the location detection system 122 includes an Inertial Measurement Unit (IMU) which is a device that measures and reports an object's specific force, angular rate, and sometimes the magnetic field surrounding the object. For example, an IMU may include accelerometers to measure linear acceleration along multiple axes, gyroscopes to detect rotational movement (angular velocity) around those axes, magnetometers to measure the magnetic field, aiding in orientation and heading, or other types of sensors. In some implementations, the IMU is configured to provide information for navigation, stabilization, and motion tracking when the location detection system is jammed by navigation interference signals. In some instances, output from the IMU can be used to determine the geolocation of the mobile platform when the navigation interference signals are detected, and the location detection system is not available to determine the geolocation information. In some instances, the IMU can be used in another manner.

[0049] In some implementations, the location detection system 122 can further utilize non-satellite navigation signals including terrestrial communication or ranging signals, such as cellular, Wi-Fi, Bluetooth, or ultra-wideband (UWB) transmissions, which can be processed to determine relative position or signal-based localization information. Environmental reference signals, including magnetic field variations, optical landmarks, acoustic or ultrasonic beacons, or radar and lidar reflections, may be employed to provide additional positional references, particularly in interference-affected regions. Onboard inertial sensors, including accelerometers, gyroscopes, barometers, and odometers, may supply dead-reckoning data that is fused with received navigation signals to estimate position, velocity, and attitude. In some examples, the location detection system 122 can be configured to fuse data from one or more of these sources to maintain accurate and continuous navigation in environments where GNSS signals are degraded, obstructed, or unavailable.

[0050] In some implementations, the laser system 112, the photonic integrated circuit system 114, and the system-on-chip 116, the power supply 118, the user interface 120, the location detection system 122, and other devices or components of the control system 104 may be housed in a housing of the control system 104. In some implementations, the vapor cell sensor 102 resides outside the housing of the control system 104. In some instances,the example QSS-assisted navigation system 100 may be disposed on a mobile platform, such as a service van. The mobile platform may be operable to transport at least the vapor cell sensor 112 of the QSS-assisted navigation system 100 to other measurement locations. In some instances, the QSS-assisted navigation system 100 may remain fixed in place relative to a cellular base station, radar station, or other emitter sources, allowing changes in emission over a period of time to be more easily tracked. In some instances, components of the QSS-assisted navigation system 100 can be powered by the power supply 118. The power supply 118 may be a battery unit for remote field testing.

[0051] In some instances, the example QSS-assisted navigation system 100 may be operated under a coarse scan mode or a time-dependent signal acquisition mode. In some examples the two modes may be operated and switched between each other in an automatic fashion. For example, the example QSS-assisted navigation system 100 can be configured to perform slow scanning real-time spectrum analyzer (RTSA); and may switch to the rapid scanning mode by operation of an agile laser system as one of the coupling lasers (e.g., a coupling laser probe system), allowing the QSS-assisted navigation system 100 to rapidly switch between Rydberg states. Examples of the coupling laser system are described in U.S. Patent No. 11,658,461. In some instances, the agile laser allows simultaneous generation of multiple coupling laser frequencies so as to sense several RF frequencies at the same time. The different frequencies of the coupling laser can be routed to the same vapor cell or different ones. The agile coupling laser enables the QSS-assisted navigation system 100 to be reconfigured in order to adapt to a particular task. For example, in electronic warfare spectrum sensing, the example QSS-assisted navigation system 100 can perform fast scans to identify regions of interest between UHF-band and W-band. Once the areas of interest are known, the example QSS-assisted navigation system 100 can be configured to focus on the area of interest with longer dwell times or to focus on acquiring the signals of interest in real-time. Data can be sent to a data processing center to decode or interpret to plan operations.

[0052] In some implementations, the systems and techniques described here can significantly improve the resilience of navigation systems for unmanned and manned aerial, terrestrial (both land and sea) and space vehicles. Unmanned vehicles haveexistential dependence on their navigation systems as they are remotely controlled. The resilience of navigation systems is fundamentally important to their operation. The precise identification of their position enables them to spatially map quantities, based on their sensor suite, and remote operation requires their position, velocity and angular velocity, linear and angular accelerations, and time to be known so that an operator can precisely direct them to their target along a planned trajectory. GNSS is also important for manned vehicles, as demonstrated by the widespread use of mapping apps on phones for travel.

[0053] In some instances, the systems and techniques described in the present application can provide a number of advantages and improvements to a traditional navigation system. For example, in some cases, a QSS-assisted navigation system has ultrabroad carrier bandwidth, is not easily damaged by jamming, can agilely change its detection frequency using a single sensor, is practically non-detectable due to its electromagnetic transparency, can scan a broad bandwidth like 40 GHz in seconds to acquire signals, is, accurate and repeatable, supports multiple sensors that are noninterfering with other RF and electronic systems, is straightforward to operate and has a SWaP-C suitable for using in drones and transportation vehicles. A QSS-assisted navigation system can be ideal for sensing the new diverse navigation signals (also current ones) either one at a time or multiple frequency signals simultaneously, making it a powerful device for navigation applications, particularly for interference-affected areas, due to a diverse range of reasons such as weather, jamming and spoofing.

[0054] In some implementations, the systems and techniques described here enable a broad range of detection of frequencies within the GNSS signal frequency bands generated by satellites from a variety of constellations and orbits (e.g., LEO approximately 2,000 km, MEO approximately 20,000 km, etc.). In some instances, the QSS-assisted navigation system can detect signals from one or more satellites not meant for GNSS-based navigation. The QSS assisted navigation system can create fundamental resilience and survivability (redundancy and fail-over) for the GNSS navigation system in the presence of a jamming signal, spoofing signal and weather. In some cases, QSS-assisted navigation systems carried by multiple vehicles can communicate with each other, can help one of these UAVs when it loses GNSS signalsby temporarily leveraging other UAVs in its network to maintainapproximate navigation information; for example, the mobile platforms may form a local network to exchange information.

[0055] FIG. 2 is a schematic diagram 200 showing an example mobile platform 202 navigating through an environment. The mobile platform 202 can be an unmanned or manned aerial, terrestrial or space vehicle. For example, the mobile platform 202 may include an aerial vehicle, a terrestrial vehicle, a marine vehicle, or a spaceborne vehicle, and may be configured for either unmanned or manned operation. In some instances, the mobile platform 202 generally includes a propulsion subsystem, a drive or actuation subsystem, a control subsystem, and one or more power supply units. The mobile platform 202 includes a QSS-assisted navigation system which may be implemented as the example QSS-assisted navigation system 100 shown in FIG. 1 or in another manner.

[0056] In some instances, the propulsion or drive subsystem may include one or more motors, engines, thrusters, reaction wheels, propellers, rotors, or wheel assemblies configured to provide translational and / or rotational movement of the platform. The control subsystem may include one or more processors, controllers, flight computers, motor drivers, or drive control circuits configured to regulate the operation of the propulsion subsystem based on navigation commands, sensor feedback, and mission parameters. The QSS-assisted navigation system may include a location detection system which may include inertial measurement devices, Global Navigation Satellite System (GNSS) receivers, altimeters, star trackers, cameras, or other sensors configured to determine position, orientation, and movement of the platform. In some examples, the control subsystem is further configured to autonomously operate the platform according to pre-programmed instructions, real-time sensor inputs, remote operator commands, or a combination thereof.

[0057] In some implementations, the QSS-assisted navigation system of the mobile platform 202 can perform RF signal detection / mapping operation (e.g., the operations in the example process 300 shown in FIG. 3 or in another manner). The QSS-assisted navigation system communicates with the control subsystem of the mobile platform 202 providing navigation data to allow autonomous operations and navigation. The QSS- assisted navigation system of the mobile platform 202 can be used to operate the mobileplatform 202 in the environment to identify boundaries 208 between interference-free regions 210 and interference-affected regions 206. The navigation data (e.g., based on characterization of the detected RF signals, information associated with the detected navigation interference signal, etc.) produced by the QSS-assisted navigation system can be used to guide the mobile platform 202 toward a target location 204. The QSS-assisted navigation system can determine a spatial mapping of the navigation interference signals, which can be stored and used to guide other mobile platforms navigating through the same environment. In some implementations, the QSS-assisted navigation system of the mobile platform 202 is configured to produce a spatial interference map which includes intensities and locations of the navigation interference signals detected. The spatial interference map is stored in a memory unit of the control system (e.g., a navigation database) for use in subsequent navigation operations of the mobile platform. In some instances, the spatial interference map or other information related to the navigation interference signal identified by operation of the mobile platform 202 and the QSS-assisted navigation system can be transmitted to a second mobile platform which configured its own navigation based on the information received. In some instances, the spatial interference map or other navigation data can be used in another manner, such as at a central command and control center.

[0058] FIG. 3 is a flow chart showing an example QSS-assisted navigation process 300. The example process 300 can be used, for example, to operate a mobile platform (e.g., the mobile platform 202 shown in FIG. 2) equipped with a QSS-assisted navigation system to navigate in an environment. The QSS-assisted navigation system can be implemented as the example QSS-assisted navigation system 100 in FIG. lor another type of QSS-assisted navigation system. For instance, the example process 300 allows the use of a QSS-assisted navigation system to detect electromagnetic signals that can interfere with one or more navigation signals, e.g., navigation interference signals. In some instances, the navigation signals may be at different frequency bands, e.g., GPS signals at LI band (1575.42 MHz), L2 band (1227.60 MHz) and L5 band (1176.45 MHz), and Galileo signals at El band (1575.42), E5a band (1176.45 MHz), and E5b band (1207.14 MHz). In certain examples, a navigation interference signal may be a jamming signal, a spoofing signal, or other types of RF signalsthat can interfere with the operation of the location detection system and prevent the location detection system to accurately determine the geolocation and timing information.

[0059] In some instances, the example process 300 can detect electromagnetic signals, determine characteristics of the detected RF signals, and identify the navigation interference signals based on the determined characteristics. In some instances, the example process 300 can perform a spatial mapping of the navigation interference signals in the environment, and identify boundaries between interference-free regions (where GNSS signals can be received with no or acceptable level of interference) and interference- affected regions (where navigation interference signals significantly affect the operation of the GNSS-based navigation system). For example, the mobile platform 202 of FIG. 2 equipped with the QSS-assisted navigation system 100 shown in FIG. 1 can be operated and used to identify the boundary 208 between interference-free regions 210 and interference- affected regions 206 as shown in FIG. 2. The example process 300 can be used to guide the mobile platform 202 toward a target location 204. The spatial mapping of the navigation interference signals can be stored and used to guide other vehicles navigating through the same region.

[0060] The example process 300 may include additional or different operations, including operations performed by additional or different components, and the operations may be performed in the order shown or in another order. In some implementations, one or more operations in the example process 300 can be performed by a computer system, for instance, by a digital computer system having one or more digital processors (e.g., signal processing apparatus 110 of the QSS-assisted navigation system 100 in FIG. 1) that execute instructions (e.g., instructions stored in a memory unit of the control system 104 in FIG. 1).

[0061] At 302, geolocation information is obtained. The geolocation information may include location coordinates (e.g., latitude, longitude, altitude) as well as other types of information such as, for example, speed or velocity data, timing information, etc. The geolocation information is associated with the mobile platform and includes information or data generated by a location detection system of the mobile platform. In the exampleprocess 300, the geolocation information includes position information (e.g., spatial coordinates) that represent the location of the mobile platform.

[0062] In some instances, the geolocation information can be obtained by operation of a location detection system of the QSS-assisted navigation system. In some instances, the location detection system may be a Global Navigation Satellite System (GNSS) receiver configured to provide the geolocation information of the mobile platform 202. For example, the location detection system in the communication module 112 of the QSS-assisted navigation system 100 may be compatible with at least one of the following technologies, Global Positioning System (GPS), GLObal Navigation Satellite System (GLONASS), Galileo, or Beidou. Another type of location detection system may be used to provide location information. In some instances, the location detection system is configured to determine geolocation information (e.g., latitude, longtitude, and altitude) of the mobile platform and thus the one or more vapor cell sensors of the QSS-assisted navigation system. In some instances, the location detection system may be included in the communication module 112, the control system 104, or other parts of the QSS-assisted navigation system 100.

[0063] In some instances, the location detection system can search and identify satellite signals based on the unique coarse / acquisition code with a certain frequency band. In some instances, the location detection system can identify satellite signals from multiple frequency bands. In some instances, the location detection system can compensate for changes in relative locations between the mobile platform 202 and the satellites and can lock onto the carrier phase of the signal. Once the location detection system establishes the communication with a satellite, it can start decoding the navigation message which includes data such as satellite ephemeris, almanac, time and satellite health status. In some instances, the location detection system can calculate the time delay between when the satellite signal was sent and when it was received; and the time delay can be used to determine the distance between the mobile platform and the satellite. In some instances, the location detection system can establish communication with multiple satellites to obtain signals to accurately determine the 3D position. In some instances, the location detection system can solve a set of equations to determine the 3D position, based on the distance calculated from the time delay. In some instances, one or more satellites can beused to correct the location detection system’s clock to ensure accurate and precise timekeeping. In some instances, the position and timing information may be obtained in another manner.

[0064] In addition to GNSS, the location detection system may further utilize nonsatellite navigation signals including terrestrial communication or ranging signals, such as cellular, Wi-Fi, Bluetooth, or ultra-wideband (UWB) transmissions, which can be processed to determine relative position or signal-based localization information. Environmental reference signals, including magnetic field variations, optical landmarks, acoustic or ultrasonic beacons, or radar and lidar reflections, may be employed to provide additional positional references, particularly in interference-affected regions. Onboard inertial sensors, including accelerometers, gyroscopes, barometers, and odometers, may supply dead-reckoning data that is fused with received navigation signals to estimate position, velocity, and attitude. In some examples, a location detection system is configured to fuse data from one or more of these sources to maintain accurate and continuous navigation in environments where GNSS signals are degraded, obstructed, or unavailable.

[0065] In some instances, the geolocation information can be stored locally in the memory unit of the QSS-assisted navigation system. In some instances, the geolocation information can be transmitted wirelessly to a remote node (e.g., a user device, an external monitoring system 134, another mobile platform, or other remote node). In some instances, the geolocation information can be transmitted together with detection results (e.g., properties of detected RF signals associated with the geolocation and timing data) to the remote node.

[0066] At 304, output optical signals from one or more vapor cell sensors are obtained. In some implementations, the QSS-assisted navigation system on the mobile platform can be configured according to the frequency bands in which navigation signals reside. In some instances, the QSS-assisted navigation system is configured according to settings of the location detection system. For example, a GPS receiver may first scan the environment to detect and lock onto signals transmitted by GPS satellite’s unique coarse / acquisition code within a specific frequency band. The GPS receiver can identify the satellite signals based on the specific code each satellite transmits. After identifying the GPS signal, the QSS-assisted navigation system may be configured by inputting the operating frequency of the GPS signal through an interface (e.g., an interface of the communication module 112). In some instances, the QSS-assisted navigation system may be configured to scan a frequency range around the carrier frequency. For example, for a satellite operating at the LI frequency (1575.42 MHz), the QSS-assisted navigation system can be configured to scan a frequency range from 1200 to 1800 MHz to search for other signals that could possibly interfere with the GPS signals emitted from the satellite. In some instances, the QSS- assisted navigation system can be configured to scan a different range based on operating frequencies of the satellites. For example, a coupling laser in the QSS-assisted navigation system or one of the coupling lasers when the QSS-assisted navigation system includes more than two lasers can be tuned to a Rydberg state with a resonance frequency overlapping with the operating frequency of the satellites. In some instances, the QSS- assisted navigation system may be tuned to allow an interaction between the vapor of Rydberg atoms in the vapor cell sensor and the navigation signals transmitted by one or more navigation signal sources.

[0067] In some implementations, two or more lasers are configured to generate input optical signals that include at least one coupling optical signal and at least one probe optical signal. In some instances, the one or more input optical signals are locked to a stable, narrow bandwidth reference such as a frequency comb signal, interferometer, atomic or molecular absorption line, or another type of reference. The two or more laser sources are in optical communication with the one or more vapor cell sensors through a transmission medium (e.g., in free-space or through optical fiber) and as such, the coupling and probe optical signals can interact with the vapor having Rydberg states in the vapor cell sensors. In some implementations, the output optical signals are generated by vapor cell sensors in an array based on an interaction between the vapor in the vapor cell sensors, the RF signals having operating frequencies within the frequency ranges that the vapor cell sensors are tuned to, and input optical signals. Such interactions allow the vapor cell sensors to perform Rydberg atom-based electromagnetic signal sensing and thereby generate the output optical signals based on the coupling and probe optical signals. In some implementations, the output optical signals may represent the response of the vaporhaving Rydberg states in the vapor cell sensors to the electromagnetic signals within a frequency range of interest. In some instances, a vapor having Rydberg states can be a vapor of Rydberg atoms (e.g., Rb, Cs, etc.), Rydberg molecules (e.g., H2, 12, etc.) or possibly both. For example, the output optical signals from the vapor cell sensor can be generated using electromagnetically induced transparency (EIT) or electromagnetically induced absorption (EIA). In some instances, a sub-Doppler method can be used to obtain higher spectral resolution in the Autler-Townes regime and higher sensitivity.

[0068] In some instances, the coupling or probe optical signal can be scanned to obtain the output optical signals. In certain examples, the probe optical signal can be used to generate a frequency comb signal in an optical heterodyne setup to obtain the output optical signals. In some instances, pulsed readout can be used to acquire the transmitter signals, perhaps in combination with laser frequency changes In some instances, the coupling optical signal of the EIT or EIA-like system can be tuned to different Rydberg states to target different RF frequencies. In some instances, spectral signals within a bandwidth of ~250 MHz of the target frequency can be detected by analyzing the optical spectra for a single Rydberg transition and / or detuning the coupling and probe lasers that may be used for Rydberg atom-based sensing. The optical signal for monitoring the laser sources and keeping them stable can be routed via the waveguide through all or part of the QSS-assisted navigation system. Feedback to control the laser sources, including feed forwards, can be realized using FPGAs, analog electronics, or another processor-based system that can be controlled through a user interface and through autonomous control layers operating in different types of processors. When a frequency comb signal is used, the signal processing system of the QSS-assisted navigation system may include a real-time spectrum analyzer which can be used to detect the output optical signal. In the case of a frequency comb signal, it is not necessary to scan either of the coupling and probe optical signals to read out the first set of output optical signals, although it is possible to use scanning and a frequency comb signal in combination with each other.

[0069] In some instances, an average optical spectrum may be obtained. For example, the average optical spectrum may be obtained using a frequency comb signal, or another technique. In some instances, the results can be fit to identify navigation interferencesignals within a specified range (e.g., ~250 MHz) of the carrier frequency of the GNSS signals using a software without tuning to a different Rydberg state. For example, a navigation interference signal may include signals that can disrupt or block the communication between a GPS receiver and GPS satellites. In some instances, a navigation interference signal may have a significantly higher power compared to legitimate navigation signals which are weak by the time they reach the Earth’s surface. In some instances, a navigation interference signal may be unmodulated continuous wave with a single tone. In some instances, a navigation interference signal may have a periodic burst affecting the GPS receiver intermittently potentially allowing for partial GPS function but disrupting overall accuracy. In some instances, a navigation interference signal may be along a specific direction or at a certain area. In some instances, a navigation interference signal may be a frequency-sweeping signal that is designed to impact a wider range of frequencies or jam multiple signals. In some instances, a navigation interference signal may have other characteristics.

[0070] At 306, the output optical signals are processed to determine characteristics of an electromagnetic signal. In some instances, the QSS-assisted navigation system can be tuned across different frequency ranges by changing the wavelength of the coupling laser of the same vapor cell sensor. Both the control signals and communications signals can be analyzed and recorded to characterize the electromagnetic signal received. In some instances, the output optical signals may be received by a photodetector (e.g., in the signal processing module 110 of the example system 100 shown in FIG. 1). In this case, the photodetector senses changes in the transmission caused by the RF signals to the one or more vapor cell sensors; and converts the output optical signals to respective electrical signals. In some instances, the electrical signals are then converted (e.g., using analog-to- digital conversion circuitry, or otherwise) to digital data that can be processed on a FPGA, GPU, computer processor, or some combination thereof, including specialized hybrid processors.

[0071] In some instances, the digital data is processed to detect a navigation interference signal within the signal bandwidth. In some instances, the digital data may be used to determine information of the electromagnetic signals to determine properties thatare characteristics of navigation interference signals experienced by the vapor over a time period. For example, the digital data may be processed; and at least one of the properties of the RF signals experienced by the vapor in the time period can be identified, including a start time, a duration, an amplitude, a frequency, a polarization, a propagation direction, and other properties. In some instances, the navigation interference signal may be identified in another manner.

[0072] In some implementations, a navigation interference signal includes any electromagnetic, acoustic, or optical signal, whether intentional or unintentional, that disrupts, distorts, attenuates, or otherwise degrades the reception or processing of navigation signals used by a mobile platform’s location detection system. Such interference may affect satellite-based signals (e.g., GNSS signals such as GPS, Galileo, GLONASS, or BeiDou), terrestrial radio or communication signals (e.g., cellular, Wi-Fi, Bluetooth, or ultra- wideband transmissions), environmental reference signals (e.g., magnetic, acoustic, radar, or optical landmarks), or onboard ranging or sensor-based navigation data. The navigation interference signal may include, for example, jamming or spoofing transmissions, multipath reflections, signal absorption, or unintentional emissions from nearby electronic equipment that cause a reduction in signal-to-noise ratio, distortion of timing information, or corruption of ranging measurements. Detection or characterization of such interference signals may be used to determine interference-affected regions, to adapt signal processing parameters, or to guide transitions between interference-free regions and interference- affected regions.

[0073] In some implementations, determining the characteristics of the electromagnetic signals includes evaluating a signal quality metric associated with received navigation signals. For example, the QSS-assisted navigation system may analyze a signal-to-noise ratio (SNR), carrier-to-noise density ratio (C / No), signal correlation peak shape, or other interference indicator derived from the identified navigation interference signals. A predetermined SNR threshold value is applied to the SNR (or other metric) to distinguish regions in which navigation signals are sufficiently strong and reliable from regions in which navigation signal reception is degraded, jammed, spoofed, obstructed, or otherwise unusable. Based on whether the evaluated signal metric falls above or below the thresholdvalue, the QSS-assisted navigation system classifies corresponding portions of the operational environment as interference-free or interference-affected.

[0074] In certain examples, determining the characteristics of the electromagnetic signals includes analyzing characteristics of terrestrial, environmental, or sensor-based signals used for positioning or navigation. For example, the system may evaluate signal strength, timing stability, and multipath distortion of cellular, Wi-Fi, Bluetooth, or ultra- wideband signals, or assess consistency among such signals to detect local interference or infrastructure anomalies. For magnetic or acoustic navigation, sudden variations in measured field intensity or frequency content may indicate environmental interference or sensor corruption. When visual, radar, or lidar-based localization is employed, interference may be inferred from a loss of landmark detection, increased feature noise, or reduced correlation between consecutive frames. The location detection system may combine such assessments with inertial measurements to confirm the presence and extent of interference, thereby maintaining situational awareness and navigation continuity even in environments with degraded signal conditions.

[0075] In response to navigation interference signals not being detected, the process 300 continues with operation 308 during which the mobile platform can be operated by a user or continue with a predefined pathway. In some instances, the geolocations where navigation signals are detected and the navigation interference signals are not detected can be labeled as interference-free regions. In some instances, in response to the mobile platform moving to a new geolocation, the operations 302, 304, 306 can be repeated, e.g., output optical signals can be obtained from the one or more vapor cell sensors; and the output optical signals obtained at the new geolocation during a new time period can be processed to determine characteristics of the electromagnetic signals at the new geolocation; the characteristics of the electromagnetic signals can be evaluated to identify the presence of the navigation interference signals.

[0076] In response to navigation interference signals being detected, the process 300 continues with operation 310 during which a navigation boundary separating an interference-free region and an interference-affected region is determined. In some instances, an interference-free region refers to a spatial area in which electromagneticsignal characteristics satisfy one or more quality thresholds indicative of reliable navigation signal reception and minimal interference. Conversely, an interference-affected region may include an area in which one or more of the RF signal characteristics fall below such thresholds, thereby indicating degradation or corruption of the received navigation signal. The RF signal characteristics used to distinguish these regions may include, but are not limited to, signal-to-noise ratio (SNR), carrier-to-noise density ratio (C / No), received signal power, noise floor, spectral purity, or correlation stability. In some examples, a navigation boundary between the interference-free region and the interference-affected region may be defined as a transitional zone or contour along which at least one of the monitored RF characteristics satisfies a predefined threshold condition, such as an SNR or C / Nolevel corresponding to a minimum acceptable navigation signal quality. In some instances, a navigation boundary may dynamically shift in response to temporal or spatial variations in interference intensity, allowing the location detection system to adaptively classify operational regions as interference-free, partially degraded, or interference- affected. In addition, the system can create maps based on other parameters such as frequency of interference, strength of interference, pulse rate of interference and chirp rate of interference. Maps based on another parameter or multiple parameters are also possible.

[0077] In some implementations, in addition to defining a boundary between interference-free and interference-affected regions, the QSS-assisted navigation system may generate a spatial interference map that represents the intensities and spatial distribution of identified interference signals. The spatial interference map may be derived from measurements of RF signal characteristics, such as signal-to-noise ratio (SNR), carrier-to-noise density ratio (C / No), received power level, or spectral density, obtained from one or more sensors or navigation receivers at different locations. Each point or region within the map may be assigned an interference intensity value indicative of the degree of signal degradation or jamming strength at that location. In certain examples, the map may be represented as a two-dimensional or three-dimensional data structure defining interference gradients or contours, and may be dynamically updated in response to new measurements or detected changes in interference conditions. In some instances,the spatial interference map can be stored and used to identify interference hotspots, predict signal degradation along planned routes, and support adaptive navigation strategies that prioritize operation within interference-free regions or other subsequent navigation operations of the mobile platform.

[0078] In some instances, the geolocations where navigation interference signals are identified can be labeled as interference-affected region. In some instances, the geolocation data in the presence of the navigation interference signal may be determined by operation of an inertial measurement unit (IMU) based on the previous geolocation data and movement data (e.g., heading direction, speed, acceleration, etc.). In some instances, output from the IMU can be used to determine the current location of the mobile platform and determine position adjustment that needs to be performed in order to guide the mobile platform out of the interference-affected region and return the mobile platform to one of the previously identified interference-free regions. In some implementations, determining one or more boundaries between interference-free regions and interference-affected regions comprises evaluating a signal-to-noise ratio threshold associated with the identified navigation interference signals. The resulting boundary information and other navigation data (e.g., the interference map) may be stored, updated, or transmitted to other subsystems, the external monitoring system, or other mobile platform to guide subsequent navigation, localization, mission planning, or platform control operations.

[0079] In some implementations, QSS-assisted navigation systems include a communication module that transmits interference-related information, including detected signal characteristics, the spatial interference map, and boundary information between interference-free and interference-affected regions, to an external monitoring system. The communication module may employ wired or wireless data links, such as cellular, satellite, radio-frequency, or optical communication channels, to facilitate real-time or periodic data exchange. The transmitted information may be utilized by the external monitoring system for data fusion with measurements obtained from other mobile platforms or sensors, thereby generating a comprehensive situational awareness model of interference conditions across a broader operational area. In some implementations, the external monitoring system shares the information with a second mobile platform which configuresits own navigation operation based on the shared information. The shared information can support collaborative navigation, mission coordination, or adaptive path planning among multiple platforms, and may be used to guide overall operational decisions, update interference maps, or issue alerts to other units operating within or approaching interference-affected regions. For example, the second mobile platform is operated to navigate from an interference-affected region toward an interference-free region according to the determined navigation boundary.

[0080] As shown in FIG. 3, the process 300 continues with operation 312 during which position adjustment is performed. In some instances, in response to an identification of the presence of a navigation interference signal, a predetermined position adjustment can be performed. For example, the mobile platform can change its heading direction to a location (e.g., in a previously identified interference-free region) where a navigation signal was previously detected and then move to a new geolocation where the operations 302, 304, 306 can be repeated. In some instances, the output information including geolocation data, timing data, results based on the analysis of the output optical signals, etc. from the mobile platform may be transmitted through a wireless or wired communication to a remote node (e.g., the external monitoring system or another mobile platform).

[0081] In some instances, in response to an identification of the presence of a navigation interference signal, the control system can command the mobile platform to be operated along a direction in which the navigation interference signal becomes stronger (e.g., in the interfere-affected region). By intentionally steering the mobile platform toward regions of increased interference amplitude (for example, by adjusting heading, altitude, or speed), the system can acquire measurements over a range of locations that exhibit a larger spatial gradient in signal strength. Such motion can improve the signal-to-noise ratio for the interference signal, facilitate more accurate characterization of its spectral content and temporal behavior, and enable estimation of parameters such as direction-of-arrival or approximate source location. In this way, the mobile platform’s trajectory can be adaptively adjusted so that the QSS-assisted navigation system can obtain a richer set of measurement data, thereby enhancing the ability of the navigation system to detect, classify, localize, and ultimately mitigate the effects of the navigation interference signal. In this case, the spatialinterference map may further include the gradient, amplitude, source location, and other information of the interference signals in the interference-affected regions. During the further explore operation of the mobile platform in the interference-affected regions, the mobile platform may communicate with other neighboring mobile platforms or the external monitoring system through a distinct communication band that is not affected by the interference signals. In some instances, the mobile platform may be operated in the interference-affected regions in another manner.

[0082] Some of the subject matter and operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Some of the subject matter described in this specification can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions, encoded on a computer storage medium for execution by, or to control the operation of, data-processing apparatus. A computer storage medium can be, or can be included in, a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of one or more of them. Moreover, while a computer storage medium is not a propagated signal, a computer storage medium can be a source or destination of computer program instructions encoded in an artificially generated propagated signal. The computer storage medium can also be, or be included in, one or more separate physical components or media.

[0083] Some of the operations described in this specification can be implemented as operations performed by a data processing apparatus on data stored on one or more computer-readable storage devices or received from other sources.

[0084] The term "data-processing apparatus" encompasses all kinds of apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, a system on a chip, or multiple ones, or combinations, of the foregoing. The apparatus can include special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit). The apparatus can also include, in addition to hardware, code that creates an executionenvironment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, a crossplatform runtime environment, a virtual machine, or a combination of one or more of them.

[0085] A computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, declarative or procedural languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, object, or other unit suitable for use in a computing environment. A computer program may, but need not, correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network.

[0086] Some of the processes and logic flows described in this specification can be performed by one or more programmable processors executing one or more computer programs to perform actions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).

[0087] In a general aspect, a quantum spectrum sensing (QSS) -assisted navigation system is described.

[0088] In a first example, a quantum spectrum sensing (QSS)-assisted navigation system including a vapor cell sensor and a control system communicably connected to the vapor cell sensor resides on a mobile platform. A method of operating the QSS-assisted navigation system includes obtaining geolocation information associated with the mobile platform from a location detection system of the control system; obtaining output optical signals from the vapor cell sensor, the output optical signals being generated based on aninteraction between the vapor cell sensor and electromagnetic signals in an environment of the mobile platform; by operation of a signal processing system of the control system, identifying characteristics of the electromagnetic signals based on the output optical signals; by operation of the signal processing system, identifying the presence of navigation interference signals in the environment based on the characteristics of the electromagnetic signals; and by operation of the signal processing system, based on the identified navigation interference signals and the geolocation information, determining a navigation boundary for the mobile platform.

[0089] Implementations of the first example may include one or more of the following features. The method includes storing the spatial interference map in a navigation database for use in subsequent navigation operations of the mobile platform. Obtaining the output optical signals includes operating a laser system and a photonic integrated circuit system to generate input optical signals that interact with Rydberg states of atoms of a vapor in the vapor cell sensor, the photonic integrated circuit system includes comb generators that generate respective frequency comb signals based on the laser signals from the laser system, and the frequency comb signals enable broadband sensing of RF signals. Operating the laser system includes performing a probe laser comb readout by measuring at multiple comb frequencies simultaneously.

[0090] Implementations of the first example may include one or more of the following features. The method includes transmitting, via a communication module of the control system, information associated with the identified navigation interference signals to an external monitoring system. The mobile platform is a first mobile platform. The external monitoring system has a communication link with a second mobile platform. The external monitoring system is configured to transmit the information associated with the identified navigation interference signals to the second mobile platform. The second mobile platform configures a navigation operation based on the information.

[0091] Implementations of the first example may include one or more of the following features. The navigation interference signals include Global Navigation Satellite System (GNSS) interference signals that affect operation of the location detection system. Obtaining the geolocation information associated with the mobile platform includes inresponse to the location detection system being unable to obtain reliable navigation signals, operating an inertial measurement unit (IMU) to estimate the motion of the mobile platform. Identifying the characteristics of the electromagnetic signals includes performing frequency-domain analysis of the output optical signals. Determining the navigation boundary includes evaluating a signal-to-noise ratio threshold associated with the identified navigation interference signals. The method includes causing the mobile platform to navigate from an interference-affected region toward an interference-free region according to the determined navigation boundary.

[0092] In a second example, a quantum spectrum sensing (QSS)-assisted navigation system includes a vapor cell sensor; and a control system communicably coupled to the vapor cell sensor. The control system includes a location detection system and a signal processing system. The signal processing system is configured to perform operations including obtaining geolocation information associated with the mobile platform from the location detection system; based on output optical signals from the vapor cell sensor, identifying characteristics of electromagnetic signals in an environment of the mobile platform, the output optical signals being generated based on an interaction between the vapor cell sensor and the electromagnetic signals; based on the characteristics of the electromagnetic signals, identifying the presence of navigation interference signals in the environment; and based on the identified navigation interference signals and the geolocation information, determining a navigation boundary for the mobile platform.

[0093] Implementations of the second example may include one or more of the following features. The operations include generating a spatial interference map representing intensities and locations of the identified navigation interference signals. The operations include storing the spatial interference map in a navigation database for use in subsequent navigation operations of the mobile platform. The control system comprises a laser system and a photonic integrated circuit system. Obtaining the output optical signals includes operating the laser system and the photonic integrated circuit system to generate input optical signals that interact with Rydberg states of atoms of a vapor in the vapor cell sensor. The photonic integrated circuit system includes one or more comb generators configured to generate frequency comb signals that enable broadband sensing of theelectromagnetic signals. Operating the laser system includes performing a probe laser comb readout by measuring at multiple comb frequencies simultaneously.

[0094] Implementations of the second example may include one or more of the following features. The operations include transmitting, via a communication module of the control system, information associated with the identified navigation interference signals to an external monitoring system. The mobile platform is a first mobile platform. The external monitoring system has a communication link with a second mobile platform. The external monitoring system is configured to transmit the information associated with the identified navigation interference signals to the second mobile platform. The second mobile platform configures a navigation operation based on the information.

[0095] Implementations of the second example may include one or more of the following features. The navigation interference signals include Global Navigation Satellite System (GNSS) interference signals that affect operation of the location detection system. Obtaining the geolocation information associated with the mobile platform includes in response to the location detection system being unable to obtain reliable navigation signals, operating an inertial measurement unit (IMU) to estimate the motion of the mobile platform. Identifying the navigation interference signals includes performing frequencydomain analysis of the output optical signals obtained from the vapor cell sensor. Determining the navigation boundary includes evaluating a signal-to-noise ratio threshold associated with the identified navigation interference signals. The operations include causing the mobile platform to navigate from an interference-affected region toward an interference-free region according to the determined navigation boundary.

[0096] While this specification contains many details, these should not be understood as limitations on the scope of what may be claimed, but rather as descriptions of features specific to particular examples. Certain features that are described in this specification or shown in the drawings in the context of separate implementations can also be combined. Conversely, various features that are described or shown in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable sub-combination.

[0097] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated together in a single product or packaged into multiple products.

[0098] A number of embodiments have been described. Nevertheless, it will be understood that various modifications can be made. Accordingly, other embodiments are within the scope of the following claims.

Claims

CLAIMSWhat is claimed is:

1. A method of operating a quantum spectrum sensing (QSS)-assisted navigation system on a mobile platform, the QSS-assisted navigation system comprising a vapor cell sensor and a control system communicably connected to the vapor cell sensor, the method comprising: obtaining geolocation information associated with the mobile platform from a location detection system of the control system; obtaining output optical signals from the vapor cell sensor, the output optical signals being generated based on an interaction between the vapor cell sensor and electromagnetic signals in an environment of the mobile platform; by operation of a signal processing system of the control system, identifying characteristics of the electromagnetic signals based on the output optical signals; by operation of the signal processing system, identifying the presence of navigation interference signals in the environment based on the characteristics of the electromagnetic signals; and by operation of the signal processing system, based on the identified navigation interference signals and the geolocation information, determining a navigation boundary for the mobile platform.

2. The method of claim 1, comprising: generating a spatial interference map representing intensities and locations of the identified navigation interference signals.

3. The method of claim 2, comprising: storing the spatial interference map in a navigation database for use in subsequent navigation operations of the mobile platform.

4. The method of claim 1, wherein obtaining the output optical signals comprises operating a laser system and a photonic integrated circuit system to generate input optical signals that interact with Rydberg states of atoms of a vapor in the vapor cell sensor.

5. The method of claim 4, wherein the photonic integrated circuit system comprises comb generators that generate respective frequency comb signals based on laser signals from the laser system, and the frequency comb signals enable broadband sensing of RF signals.

6. The method of claim 5, wherein operating the laser system comprises: performing a probe laser comb readout by measuring at multiple comb frequencies simultaneously.

7. The method of claim 1, further comprising: transmitting, via a communication module of the control system, information associated with the identified navigation interference signals to an external monitoring system.

8. The method of claim 7, wherein the mobile platform is a first mobile platform, the external monitoring system has a communication link with a second mobile platform, the external monitoring system is configured to transmit the information associated with the identified navigation interference signals to the second mobile platform, and the second mobile platform configures a navigation operation based on the information.

9. The method of any one of claims 1-8, wherein the navigation interference signals comprise Global Navigation Satellite System (GNSS) interference signals that affect operation of the location detection system.

10. The method of any one of claims 1-8, wherein obtaining the geolocation information associated with the mobile platform comprises: in response to the location detection system being unable to obtain reliable navigation signals, operating an inertial measurement unit (IMU) to estimate the motion of the mobile platform.

11. The method of any one of claims 1-8, wherein identifying the characteristics of the electromagnetic signals comprises performing frequency-domain analysis of the output optical signals.

12. The method of any one of claims 1-8, wherein determining the navigation boundary comprises evaluating a signal-to-noise ratio threshold associated with the identified navigation interference signals.

13. The method of any one of claims 1-8, comprising: causing the mobile platform to navigate from an interference-affected region toward an interference-free region according to the determined navigation boundary.

14. The method of any one of claims 1-8, comprising: causing the mobile platform to navigate in an interference-affected region.

15. A quantum spectrum sensing (QSS)-assisted navigation system comprising: a vapor cell sensor; and a control system communicably coupled to the vapor cell sensor, the control system comprising a location detection system and a signal processing system, the signal processing system being configured to perform operations comprising: obtaining geolocation information associated with the mobile platform from the location detection system; based on output optical signals from the vapor cell sensor, identifying characteristics of electromagnetic signals in an environment of the mobile platform, the output optical signals being generated based on an interaction between the vapor cell sensor and the electromagnetic signals; based on the characteristics of the electromagnetic signals, identifying the presence of navigation interference signals in the environment; and based on the identified navigation interference signals and the geolocation information, determining a navigation boundary for the mobile platform.

16. The system of claim 15, wherein the operations comprise: generating a spatial interference map representing intensities and locations of the identified navigation interference signals.

17. The system of claim 16, wherein the operations comprise: storing the spatial interference map in a navigation database for use in subsequent navigation operations of the mobile platform.

18. The system of claim 15, wherein the control system comprises a laser system and a photonic integrated circuit system, and obtaining the output optical signals comprises operating the laser system and the photonic integrated circuit system to generate input optical signals that interact with Rydberg states of atoms of a vapor in the vapor cell sensor.

19. The system of claim 18, wherein the photonic integrated circuit system comprises one or more comb generators configured to generate frequency comb signals that enable broadband sensing of the electromagnetic signals.

20. The system of claim 19, wherein operating the laser system comprises: performing a probe laser comb readout by measuring at multiple comb frequencies simultaneously.

21. The system of claim 15, wherein the operations comprise: transmitting, via a communication module of the control system, information associated with the identified navigation interference signals to an external monitoring system.

22. The system of any one of claims 15-21, wherein the navigation interference signals comprise Global Navigation Satellite System (GNSS) interference signals that affect operation of the location detection system.

23. The system of any one of claims 15 - 20, wherein obtaining the geolocation information associated with the mobile platform comprises: in response to the location detection system being unable to obtain reliable navigation signals, operating an inertial measurement unit (IMU) to estimate the motion of the mobile platform.

24. The system of any one of claims 15-21, wherein identifying the navigation interference signals comprises performing frequency-domain analysis of the output optical signals obtained from the vapor cell sensor.

25. The system of any one of claims 15-21, wherein determining the navigation boundary comprises evaluating a signal-to-noise ratio (SNR) threshold associated with the identified navigation interference signals.

26. The system of any one of claims 15-21, wherein the operations comprise: causing the mobile platform to navigate from an interference-affected region toward an interference-free region according to the determined navigation boundary.

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