Changeable-gain omni-directional antenna system and methods for controlling antenna system gain.

Abstract

Disclosed herein is a changeable-gain omni-directional antenna system (10) comprising a switch (10) operable to change an antenna gain. Also disclosed herein is a method (200) for controlling antenna gain.

Description

[0001] Changeable-gain omni-directional antenna system and methods for controlling antenna system gain.

[0002] Technical field

[0003] The disclosure herein generally relates to a changeable-gain omni-directional antenna system for telecommunications and methods for controlling antenna gain.

[0004] Background

[0005] Radio communication is used in many diverse environments, for example flat open country, mountainous country, and urban areas. The antenna on a vehicle, for example, may need to be changed when the vehicle’s environment changes. For example, it may be desirable to replace a high gain antenna with a low gain antenna when the environment changes between flat open country and mountainous country. Selecting a suitable antenna for the environment may increase the signal to noise ratio, and / or provide a better match between the antenna radiation pattern and the environment. Replacing an antenna may require stopping and leaving the vehicle, disconnecting the connected antenna and connecting another antenna. This may be undesirable and / or inconvenient. Replacing an antenna may improve communication but drivers may not do so - drivers may forget to replace an antenna, not willing to be inconvenienced by replacing the antenna, or dislike the weather, for example.

[0006] Summary

[0007] Disclosed herein is a changeable-gain omni-directional antenna system comprising a switch operable to change an antenna system gain.

[0008] An embodiment comprises an antenna feed and a plurality of antennae of different antenna gains. The switch may be operable to electrically-connect a selected one of the plurality of antennae of different gains to the antenna feed. The plurality of antennae of different antenna gains may comprise at least one antenna array. The plurality of antennae of different antenna gains may comprise at least one collinear antenna array.

[0009] In the context of this document, a collinear antenna array comprises a plurality of antenna elements that are parallel and collinear. The plurality of antenna elements are for radiating and / or or receiving radio waves. The plurality of antenna elements may each be elongated. An embodiment comprises an antenna array, wherein the switch is operable to change the electrical configuration of the antenna array to change the antenna system gain. The antenna array may comprise a plurality of antenna array elements, wherein the switch is operable to electrically connect at least one antenna element of the plurality of antenna elements to the antenna feed. The switch may be operable to electrically disconnect the at least one antenna element from the antenna feed. The antenna array may comprise a collinear antenna array.

[0010] In an embodiment, the switch comprises a sensor switch. The sensor switch may comprise a tilt sensor switch. The sensor switch comprises at least one of an inertial measurement sensor (IMU) switch, gyroscope sensor switch, accelerometer sensor switch, magnetometer sensor switch, inclinometer sensor switch, attitude and heading reference system (AHRS) sensor switch, compass sensor switch, inertial navigation system sensor switch, proximity sensor switch, pressure sensor switch, temperature sensor switch, light sensor switch, humidity sensor switch, touch sensor switch, sound sensor switch and motion sensor switch.

[0011] In an embodiment, the switch comprises a manually operable switch. Alternatively, or additionally, the switch comprises an electrically operable switch.

[0012] An embodiment comprises a processor in communication with the switch. The processor may be operable to change the state of the switch, for example from an “on” state to a “off’ state. The processor may be configured to receive information. The processor may be configured to be triggered by the information to electrically operate the electrically operable switch. The information may comprise information generated by a sensor. The information may comprise at least one of location information, inclination information, compass information, radio communication network information, pressure information, humidity information, and weather information.

[0013] In an embodiment, the information is received from another processor.

[0014] An embodiment comprises a housing defining a cavity. The housing may have a fin configuration.

[0015] An embodiment comprises a whip.

[0016] An embodiment is configured for at least one of a CB band, a UHF band, a VHF band, a LMR band, a LTE band, a HaLow band, and a band within 380 MHz - 3500 MHz.

[0017] An embodiment comprises a wireless network antenna. An embodiment comprises a GNSS antenna.

[0018] An embodiment comprises a plurality of half-wavelength monopole antenna elements.

[0019] An embodiment comprises at least one of a delay line, a phasing trace and a phasing coil.

[0020] Disclosed herein is a method for changing an antenna system gain of a changeable-gain omnidirectional antenna system in accordance with the above disclosure. The method comprises determining that an antenna system gain is to be changed. The method comprises operating a switch operable to change the antenna system gain.

[0021] In an embodiment, determining that the antenna gain is the be changed comprises a processor determining that the antenna gain is to be changed.

[0022] Disclosed herein is non-transitory processor readable tangible media including program instructions which when executed by a processor causes the processor to perform a method disclosed above.

[0023] Disclosed herein is a computer program for instructing a processor, which when executed by the processor causes the processor to perform a method disclosed above.

[0024] Any of the various features of each of the above disclosures, and of the various features of the embodiments described below, can be combined as suitable and desired.

[0025] Brief description of the figures

[0026] Embodiments will now be described by way of example only with reference to the accompanying figures in which:

[0027] Figure 1 shows a side elevation view of an embodiment of a changeable-gain antenna system.

[0028] Figures 2 and 3 show side elevational and isometric views of the changeable-gain antenna system of figure 1, with an enclosure removed.

[0029] Figure 4 shows a magnified view of a distal end of the changeable gain antenna system of figure 1.

[0030] Figure 5 is a front elevational view of the changeable gain antenna system of figure 1, with the enclosure removed. Figure 6 is a magnified view of the region labelled B in figure 5.

[0031] Figure 7 is a magnified view of the rear of the region labelled B in figure 5.

[0032] Figures 8-10 show a side elevation, a rear elevation and an exploded isometric view of another embodiment of a changeable-gain antenna system.

[0033] Description of embodiments

[0034] Figure 1 shows a side elevation view of an embodiment of a changeable-gain antenna system, the antenna system being generally indicated by the numeral 10. The changeable-gain antenna system 10 comprises a switch 12 operable to change the gain of the antenna system 10 (“antenna gain”). The switch 12 has a plurality of switch positions (“switch states”). The antenna system gain is greater when the switch 12 is in a first switch position of the plurality of switch positions than a second switch position of the plurality of switch positions.

[0035] The changeable-gain antenna system 10 has an antenna axis 29, which is longitudinal. The changeable-gain antenna system 10 radiates equal radio power in all directions perpendicular to the axis 29 and has a doughnut shaped antenna radiation pattern. In the context of the present document and in the field of radio communications generally, antennas that are intended to radiate equal radio wave power in all directions perpendicular to an axis, and have a doughnut shaped antenna radiation pattern, are “omnidirectional antennas”. In use, the axis may generally be vertically arranged, and so the doughnut may be generally horizontally arranged. This arrangement may be suitable for applications where broad, consistent signal coverage is required across a wide area. Consequently, the changeable-gain antenna system 10 is an omnidirectional antenna. In the present but not necessarily all embodiments, by moving the switch 12 to the first switch position, (1) the changeable-gain antenna’s radiation pattern is relatively compressed parallel to the antenna axis 29, and (2) the antenna gain perpendicular to the antenna axis 29 is relatively greater.

[0036] The switch 12 comprises a manually operable switch in the form of a slide switch that has an actuator 13 that can be hand operated by a user, however the manually operable switch may generally take any suitable and desired form, examples of which include but are not limited to push button switches, rotary switches and toggle switches. Another embodiment comprises a sensor switch as an alternative to, or additional to, the manually operable switch 12. The sensor switch may be in the form of, for example, an electromechanical sensor switch or an electronic sensor switch. The sensor switch is in this embodiment in the form of a tilt sensor switch. Examples of tilt sensor switches include but are not limited to mercury tilt switches and tilt ball switches, which may be used as suitable and desired. Alternatively or additionally, the sensor switch may comprise at least one of an inertial measurement sensor (IMU) switch, gyroscope sensor switch, accelerometer sensor switch, magnetometer sensor switch, inclinometer sensor switch, attitude and heading reference system (AHRS) sensor switch, compass sensor switch, inertial navigation system sensor switch, proximity sensor switch, pressure sensor switch, temperature sensor switch, light sensor switch, humidity sensor switch, touch sensor switch, sound sensor switch and motion sensor switch. The sensor switch may generally be any suitable and desired sensor switch.

[0037] The antenna system 10 is generally slender and elongated. Antennas having the general configuration of the antenna system 10 are known as whip antennas. The antenna system 10 comprises a major portion 14 (“whip”) for at least one of emitting and receiving radio waves. The whip 14 comprises a housing 26 in the form of a slender elongated radome defining an internal cavity, and a closure 28 in the form of a distal radome cap 26. Another embodiment does not have an enclosure as such, and may be potted for example. The antenna system 10 comprises a base potion 16 comprising a ferrule 20 in the form of a proximal ferrule. The proximal ferrule 20 is configured to reveal the switch actuator 13. The switch 12 is attached to the proximal ferrule 20. The base portion 16 is optionally configured to be mounted to an antenna mount on a vehicle or generally any suitable object or structure, generally such that the antenna is orientated vertically. Specifically in this embodiment, depending from the proximal ferrule 20 is a threaded element 18 that may be threadingly received by the antenna mount. At the proximal end of the proximal ferrule 20 is an antenna feed 29 that can conduct a radio signal to and / or from the antenna system 10. The antenna feed 29 comprises at least one electrical conduit 28 in the form of at least one coaxial cable, which may be optionally configured for delivering electrical power to the antenna as desired or required. The electrical cable is generally but not necessarily terminated by a suitable radio-frequency (“RF”) connector, examples of which include but are not limited to type N and SMA connectors. The antenna feed 28 may alternatively take the form of, for example, a radio-frequency connector attached to the base portion 16, or generally any suitable and desired form. Power in the form of direct current (DC) power may be injected via the electrical conduit 29 or a separate (optionally DC) power input. The power can be used to run active components used for switching, or in front end radio frequency modules. The base portion 16 also comprises another ferrule 22 in the form of a distal ferrule. Attached to the proximal ferrule 20 and the distal ferrule 22, is an optional resilient element 24 in the form of an antenna spring to provide stress relief to both the antenna system 10 and the antenna mount in wind and in situations when the antenna strikes obstacles, for example tree limbs. The resilient element 24 may take any suitable or desired form, for example a rubber block.

[0038] Figures 2 and 3 show side elevational and isometric views of the changeable-gain antenna system 10 with the enclosure 26 removed, and reveal a plurality of antennae generally indicated by the numeral 30. The plurality of antennae 30 include a first antenna 32 in the form of a printed circuit board (“PCB”) antenna and a second antenna 34 in the form of a non-printed circuit board antenna, however the first antenna 32 and the second antenna 34 may both be printed circuit board or non-printed circuit board types. The antenna system 10 comprises other antenna components including electronics modules, power conversion and switching functions interconnected by cables and / or tracks. The first antenna 32 and the second antenna 34 are generally each in the form of an antenna array - in this but not necessarily in all embodiments a collinear antenna arrays - comprising a plurality of antenna elements. In the first antenna 32 and the second antenna 34, each of the plurality of antenna elements comprise monopole antenna elements that are elongated - for example, half-wavelength monopole antenna elements. Generally, however, the first antenna 32 and the second antenna 34 may be any form of suitable and desired antenna, examples of which include but are not necessarily limited to monopole, dipole and MIMO antennas. The first antenna 32 and the second antenna 34 are elongated and extend between the ends of the enclosure 26. One of the first antenna 32 and the second antenna 34 has a higher gain than the other. For example, the first antenna 32 may have around 6 dB gain, and the second antenna 34 may have around 3 dB gain, or vice versa. The switch 12 is operable to electrically connect a selected one of the first antenna 32 and the second antenna 34 to the antenna feed 28 to change the antenna gain. The antennae 32,234 may have any suitable and desired gains.

[0039] The collinear antenna arrays 32, 34 each comprise a plurality of antenna elements. The printed circuit board antenna 32, for example, includes a plurality of transmitting antenna elements 36 in the form of monopole antenna elements and a plurality of electrically intermediate delay line elements in the form of meandering phasing traces 38 (or alternatively phasing coils or generally any suitable and desired form of delay line). In use, the phasing traces 38 shift the phase of the active signal. Figure 4 shows a magnified view of the distal end of the antenna system 10, in which two transmitting antenna element 36 and phase trace 38 is best seen. In an alternative embodiment, switch such as switch 12 may be operable to change the collinear antenna array of transmitting antenna element 36 and consequently antenna gain. For example, the switch 12 may be operable to electrically disconnect and / or short circuit one or more of the plurality of transmitting antenna elements 36, or electrically disconnect and / or short circuit one of or more of the delay lines 38. That is, at least one of an antenna element and a delay line is selectively activated or deactivated (“operational state change”) by operation of the switch 12.

[0040] Consequently, at least one of the antenna’s radiation pattern and gain can by dynamically reconfigured, which may be performed in response to changed operational requirements and / or environmental conditions. Only one or some of the transmitting antenna elements 36 of an array may be activated and thus the radiation pattern and gain changed. A longer array with more active elements generally has higher gain and a more compressed radiation pattern. Generally, the collinear antenna arrays may be changed in any suitable and desired way. Consequently, embodiments of a changeable-gain antenna may optionally have (1) more than two antenna gain values, and / or (2) not require one of the first antenna 32 and the second antenna 34.

[0041] Figure 5 is a front elevational view of the changeable gain antenna system 10 revealing a plurality of electronic components 40-50 mounted to the circuit board antenna 32 in the region labelled B. Figure 6 is a magnified view of the region labelled B in figure 5, and figure 7 is a magnified view of the rear of the region labelled B in figure 5. The electronic components 40-50 comprise non-transitory processor readable tangible media 40 in the form of flash memory, a microcontroller 42 in the form of an ESP32, an inclination sensor 44, a global navigation satellite system (“GNSS”) receiver 46, a radio frequency switch intra printed circuit board control 48 and a radio frequency switch 50 in the form of, for example, a PIN diode based SPDT RF switch or generally any suitable radio frequency switch for switching between the printed circuit board antenna 32 and non-printed circuit board antenna 34. The radio frequency switch 50 is electrically operable to change antenna gain. The radio frequency switch 50 is in signal communication with the non-PCB antenna via signal cable 52 or a signal PCB trace. This cable 52 or PCB trace can optionally be configured to minimise RF interference of the antenna components. Electrical traces on the PCB connect the plurality of electronic components 40-50 as required. The electronic components 40-46 and the PCB constitute a processor, in which the microcontroller 42 is in signal communication with the flash memory 40, which stores a computer program comprising program instructions that when executed by microcontroller 42 causes the processor to perform an embodiment of a method for controlling antenna gain. In a step of the method, the processor receives information. The information is in the form of, for example, sensor information in the form of inclination information from the inclination sensor 44 and / or navigation information from the GNSS receiver 46, or generally any suitable information. Figure 4 includes a GNSS antenna 51 in signal communication with the GNSS receiver 46. In another step, the processor processes the information, whereby the processor is triggered by the information, to operate an electronically operable switch 49, which in this but not necessarily in all embodiments comprises the radio frequency switch intra printed circuit board control 48 and a radio frequency switch 50. Other information the microcontroller may receive and use to determine antenna gain includes but is not necessarily limited to compass information from an onboard electronic compass, radio communication network information, and weather information. At least one of the gain and radiation pattern of the changeable gain antenna can be changed in response to sensor, navigation, received information or other information, for example signal interference information. In some embodiments, at least one of the radiation pattern and the gain can be changed without manual and / or mechanical reconfiguration.

[0042] The processor may control the antenna gain using the following examples of information:

[0043] • Location

[0044] • Inclination

[0045] • Vehicle heading

[0046] • Map information that can be stored in the flash memory 40, which can include local environment information, for example the location of trees, buildings, urban areas, hills, and / or water

[0047] • Likely or actual status of a network, bands and carrier frequencies

[0048] • Generally, any suitable and desired information.

[0049] Optionally, the changeable-gain antenna system 10 is configured to receive the information from another processor, for example a personal computation device, examples of which include but are not limited to a smart phone, tablet computer and personal computer. In this case, the changeable gain antenna system 10 may not have the inclination sensor and GNNS IC receiver, for example. The information received from the other processor is generally but not necessarily received via a wireless network or cable, examples of which include Wi-Fi™ and Bluetooth™. The changeable-gain antenna system 10 optionally comprises one or more wireless network antenna - in this embodiment printed on the PCB - to communicate with the wireless network. Optionally, embodiments of the method for controlling the antenna gain can be executed at least in part by the other processor. In this case, the microcontroller 42 can optionally implement antenna gain instructions received from the other processor. The other processor can optionally have a user interface operable by a user to cause the other processor to send antenna gain instructions to the changeable-gain antenna system 10. Examples of antenna gain instructions include but are not limited to “use the low gain antenna”, “use the high can antenna”, “use the other antenna” and “use antenna n”, where n is an identifier. Closure 28 can optionally comprise lights for one or more of antenna status indication and illumination. The closure 28 can comprise power terminals, for example 5 V pins.

[0050] Figures 8-10 show side elevation, rear elevation and exploded views of another embodiment of a changeable-gain antenna system 100, where parts similar and / or identical in form and / or function to those in figures 1-7 are similarly numbered. The housing 26 has a fin, rather than whip, configuration. The housing 26 may be mounted to the exterior of the roof of a vehicle, for example. Embodiments may generally have any suitable and desired configuration.

[0051] The disclosed embodiments of a changeable-gain antenna system 10,100 may generally be configured for any suitable and desired communications band and communication protocols. Example communication bands include: two-way radio bands associated with vehicles and / or citizens band (CB) radios; very-high frequency (VHF) bands; ultra-high frequency (UHF) bands, land mobile radio (LMR) bands, a long-term evolution (LTE) communications network band, a Wi-Fi HaLow band, a Wi-Fi band, and bands generally within but not necessarily limited to 30 MHz - 3500 MHz.

[0052] Embodiments of changeable-gain omni-directional antenna systems 10,100 disclosed herein can have their antenna system gain changed by embodiments of a method for controlling antenna system gain. Figure 11 shows a flow diagram for an embodiment of the method 200. In a step 202, it is determined that an antenna system gain is to be changed. In another step 204, a switch - 12 or 50 for example - is operated to change the antenna system gain. The step 202 of determining that an antenna system gain is to be changed can be performed by the processor. The step of operating the switch 50 can be performed by the processor. Alternatively, or additionally, the step of determining that the antenna gain is to be changed can be performed by a sensor, for example a sensor switch 12. Embodiments of the antenna system 10,100 can be suitably configured for the selected embodiment of the method. For example, embodiments may optionally comprise one or more of a tilt sensor, an inclination sensor, an inclinometer, a hygrometer, and a barometer. The processor can optionally comprise geographical (“map”) information.

[0053] Non limiting examples of embodiments of a method for controlling an antenna system gain of an omnidirectional antenna system 10,100 are now provided

[0054] In a first example embodiment of a method for controlling the antenna system gain, the high gain antenna is the default, which may be encoded into the processor. When inclination information generated by the tilt switch and / or inclination sensor indicates that the vehicle has an inclination greater than a threshold inclination, the low gain antenna is activated, for example by a tilt switch or a processor operating a radio frequency switch. The high gain antenna is activated when the inclination information indicates that the inclination is again less than the threshold inclination.

[0055] When traveling over varying terrain, the gain of the antenna system can be dynamically changed based on the road gradient to provide improved communication efficacy. The antenna has two predetermined gain settings: a low-gain setting of 2.1 dBi and a high-gain setting of 6.5 dBi. These gain settings correspond to different vertical beamwidths for adapting to terrain-induced changes in the radio signal propagation environment. The vertical beamwidth of the antenna system at each gain setting is calculated based on a formula that considers the speed of light, the operating frequency, and the effective diameter of the antenna aperture. Specifically, the vertical beamwidth is derived by multiplying a constant angle by the ratio of the speed of light to the product of the frequency and the effective diameter of the antenna system, with adjustments for each gain setting reflecting the different focusing capabilities of the antennas within the omnidirectional antenna system.

[0056] For the low-gain setting, assuming an effective aperture influenced by the lower gain, the vertical beamwidth ranges approximately from 70 to 90 degrees. This wider beamwidth generally but not necessarily provides more robust coverage in environments where signal obstructions are common, such as urban settings with high building densities. Conversely, for the high-gain setting, the narrower vertical beamwidth, for example between 25 to 40 degrees, is achieved by calculating with a smaller effective diameter due to the higher focusing capability of the high-gain setting. This narrower beamwidth may be preferred for open, less obstructed terrains where line-of-sight communication is predominant.

[0057] The antenna system includes an inclinometer in signal communication with the processor to measure the gradient of the road on which the vehicle travels. The antenna's gain is adjusted based on the gradient measurement. When the inclinometer detects a road gradient within, say, ±5 degrees of horizontal, indicative of relatively flat terrain, the processor causes the antenna system gain to be set to the high-gain mode. This setting generally but not necessarily enhances the propagation distance over flat terrains by focusing the signal more narrowly and horizontally. Conversely, when the inclinometer reading exceeds, say, ±5 degrees, suggesting steep inclines or declines, the processor switches the antenna system gain to the low-gain mode. This adjustment generally but not necessarily increases the vertical beamwidth, thereby enhancing the vertical coverage and compensating for elevation changes, which may improve communication in hilly or mountainous areas.

[0058] In a second example embodiment of a method for controlling the antenna system gain, the low gain antenna is the default because the vehicle is used mostly in built up areas, where buildings may negatively impact the performance of a high gain antenna. When location information generated by the GNNS receiver 46 is corelated with onboard map information stored in the flash memory 40 by the processor, and the processor determines that the vehicle is outside of a metropolitan area, the high gain antenna is activated by the processor operating the radio frequency switch. The low gain antenna can be activated by the processor when it is similarly determined that the vehicle is again inside a metropolitan area.

[0059] In this second example, it is possible to dependently control antenna system gain on geographic location information. Integrated into the vehicle, the omnidirectional antenna system 10,100 automatically switches between a default low-gain setting and a high-gain setting when the vehicle's detected location crosses defined metropolitan boundaries, which generally but not necessarily improves antenna performance for varying environmental conditions.

[0060] The default low-gain setting of 2.1dBi is generally but not necessarily suited for urban operations where high building densities often lead to signal reflection and diffraction. Resulting multipath interference is generally detrimental to high-gain antennas. The broader vertical beamwidth associated with the low-gain setting enhances signal coverage in complex urban environments, mitigating issues from obstructions and reflecting surfaces. Conversely, the high- gain setting of 6.5dBi is activated when the vehicle leaves a metropolitan area. This setting utilizes a narrower vertical beamwidth that focuses the signal more effectively over longer distances, which may be better for rural or open areas with minimal obstructions, thus improving the quality and reach of communication.

[0061] The antenna system 10,100 optionally integrates a GNSS receiver with onboard flash memory, which optionally stores extensive map information delineating metropolitan from nonmetropolitan areas. The vehicle’s communication system incorporates embedded control logic that processes real-time location data provided by the GNSS receiver. This data is continuously cross-referenced with the stored map information to determine the vehicle's immediate environmental context.

[0062] The processor continuously monitors GNNS information indicative of the vehicle's geographical position that is generated by the GNSS receiver. Upon detecting that the vehicle has moved outside the boundaries of a metropolitan area, the system automatically switches to the high-gain setting to utilize the clearer propagation paths available in rural or open areas. Conversely, when the vehicle re-enters a metropolitan area, the GNSS and map correlation trigger the system to revert to the low-gain setting. The broader vertical beamwidth better handles the complex signal interactions caused by urban structures, ensuring more reliable communication despite the challenging conditions.

[0063] In a third example embodiment of a method for controlling the antenna gain, the high gain antenna is the default because the vehicle is mostly used on a farm. When location information generated by the GNNS receiver 46 is corelated with onboard map information stored in the flash memory 40 and it is determined that the vehicle is within an area with high RF noise - as measured by SNR or SINAD for example - the low gain antenna is activated. The high gain antenna can be again activated when it is similarly determined that the vehicle is outside the area with high RF noise.

[0064] In this embodiment, for vehicles typically operating within expansive agricultural settings, the default configuration includes a high-gain antenna for broad and open landscapes, for example farms. This antenna is generally for extending communication reach and enhancing signal clarity over vast, unobstructed areas, for the effective management and operation of agricultural activities.

[0065] The effectiveness of the high-gain antenna, however, diminishes in urban or crowded environments where its heightened sensitivity and extended reach become counterproductive. In such environments, the high-gain antenna is prone to capturing excessive RF signals from a variety of local sources, leading to an accumulation of unwanted signals. This clutter complicates the discernment and processing of relevant signals, thus reducing communication efficiency.

[0066] To address this inefficiency and ensure optimal communication performance across varied environments, the system can dynamically adjust the antenna gain based on real-time evaluations of SNR (Signal-to-Noise Ratio) or SINAD (Signal-to-Interference-plus-Noise-and-Distortion Ratio) measurements. These metrics are for assessing the quality of the communication channel and the level of radio frequency noise in the environment.

[0067] The vehicle's GNSS receiver, in conjunction with onboard flash memory storing detailed map data, continuously monitors the vehicle’s geographic location and the surrounding radio frequency environment. It evaluates the SNR or SINAD values in real-time, which reflect the quality of the signal in relation to the background noise and interference. In high RF noise areas typically found in urban settings, SNR and SINAD values tend to drop, signalling a degradation in signal quality due to increased interference.

[0068] When a drop in SNR or SINAD indicates that the vehicle has entered a high RF noise area, the system switches from the high-gain to the low-gain antenna. The low-gain antenna, with its more limited range and reduced sensitivity, mitigates the impact of local signal clutter by focusing on maintaining clear communication with nearby sources only, thereby improving the overall signal integrity.

[0069] As the vehicle exits the high RF noise area and the SNR or SINAD levels improve, indicating a cleaner RF environment typical of rural areas, the system automatically reactivates the high-gain antenna. This switch back is predicated on the detection of a restored signal environment where the benefits of the high-gain antenna - longer reach and enhanced clarity - are once again advantageous.

[0070] In a fourth example embodiment of a method for controlling the antenna gain, the default setting is to use the high gain antenna on all bands. When location information generated by the GNNS receiver 46 is corelated with onboard map information stored in the flash memory 40 and it is determined that the vehicle is within an area known to have a strong signal for a frequency band in use, the low gain antenna is activated.

[0071] An illustration of this embodiment uses the Wi-Fi 802.1 lax standard for long range Wi-Fi, and generally but not necessarily a high-gain antenna is used by default. This arrangement generally improves signal reception and transmission range, which is crucial in remote or rural areas where Wi-Fi access points are sparse. The Wi-Fi 802.1 lax standard, notable for its efficiency in high- density scenarios and enhanced throughput, makes this approach beneficial in terms of connectivity and network performance.

[0072] The system's core functionality revolves around a GNSS receiver integrated with onboard flash memory, which stores detailed map data, including Wi-Fi signal strength measurements across different regions. These measurements are expressed in dBm (decibel-milliwatts), a standard unit for gauging Wi-Fi signal strength. The GNSS receiver continuously monitors the vehicle's precise geographic location and correlates this location data with the Wi-Fi signal strength information from the maps. Employing a high-gain antenna in areas with strong Wi-Fi signal strength, however, particularly in urban settings, can lead to suboptimal performance. The issue arises because high-gain antennas, while generally preferred for extending reach in low-signal areas, also have a broader reception range that can pick up extraneous signals from other wireless networks. This can include signals from clients and access points that are not part of the intended network. The excessive sensitivity results in the antenna receiving and processing signals that are irrelevant, thus creating unnecessary noise and potential interference within the vehicle’s Wi-Fi system.

[0073] In urban or densely populated areas where Wi-Fi signals are strong and pervasive, a high-gain antenna can inadvertently capture these signals, leading to a cluttered communication channel. This scenario is detrimental because it increases the likelihood of overlapping network frequencies and causes the system to deal with a high volume of data that does not pertain to the vehicle's operational network. Such situations can reduce the overall network efficiency and degrade the quality of the connection due to increased packet collisions and interference.

[0074] To address this, the system is designed to switch to a low-gain antenna when it detects that the vehicle has entered an area with strong Wi-Fi signals. The switch is triggered when the dBm readings, as recorded in the onboard maps, exceed a predetermined threshold indicating robust signal coverage. The low-gain antenna may minimize the pickup of unwanted signals by focusing more directly on the preferred connection points, thus maintaining a cleaner and more stable network environment.

[0075] The antenna gain can be dynamically managed based on real-time evaluations of signal strength and environmental conditions. If the vehicle exits a high-signal area and the dBm measurements fall below the set threshold, indicating weaker signal conditions, the system will reactivate the high-gain antenna to ensure continued robust communication capabilities. This dynamic adjustment may not only enhances network reliability and performance across varying environments but may also improve the vehicle's Wi-Fi system to operate efficiently, minimizing interference and conserving network resources.

[0076] A fifth example embodiment of a method for controlling antenna gain aims for consistent and reliable communication for vehicles operating in environments with varying terrestrial network coverage. In this example embodiment, the antenna system is equipped to dynamically switch between terrestrial LTE networks and satellite LTE services, such as LEOSat LTE, depending on the vehicle's location and the availability of network coverage. The system incorporates a communication module that integrates both terrestrial and satellite LTE capabilities. This module is connected to an adaptable antenna system capable of adjusting its configuration to either terrestrial or satellite signals. The core of this system's functionality is governed by an advanced algorithm that processes real-time data from a GNSS receiver. This receiver, in conjunction with onboard mapping information and network coverage map information stored in the vehicle’s onboard flash memory, continually assesses the signal strength and availability of the terrestrial LTE network.

[0077] As the vehicle travels, particularly in remote or rural areas where terrestrial network coverage is known to be unreliable or non-existent, the system actively monitors the quality of the terrestrial LTE connection. Signal strength thresholds are predefined in the system to determine the adequacy of terrestrial coverage. If the signal strength falls below these thresholds, indicating poor or no terrestrial coverage, the system triggers a switch to a satellite LTE service, specifically configured for optimal performance with LEOSat LTE.

[0078] LEOSat LTE, being part of a low Earth orbit satellite network, generally provides broader coverage and more reliable connectivity in areas beyond the reach of terrestrial networks. The antenna adjusts its gain and can optionally adjust its orientation to align optimally with the satellite's position, improving the signal reception from the satellite network. This switch not only ensures that the vehicle maintains uninterrupted connectivity but also optimizes the data transmission rates and reduces latency, leveraging the high-throughput capabilities of LEOSat LTE.

[0079] Conversely, when the vehicle re-enters an area with robust terrestrial LTE coverage, the system, still leveraging the real-time data from the GNSS receiver, detects the improvement in terrestrial signal strength. Upon confirming that the terrestrial network signal surpasses the set threshold for reliable connectivity, the antenna system reconfigures itself to optimize for the terrestrial LTE signals once more. This reconfiguration involves adjusting the antenna gain to a setting that is more suitable for capturing terrestrial signals, which are typically stronger and less variable than satellite signals when within coverage zones.

[0080] This dynamic adjustment of the antenna configuration between terrestrial LTE and satellite LTE services ensures that the vehicle can maintain the best possible connectivity regardless of its geographical location. By automating the switching process based on the detected network signal strengths and coverage data, the system enhances communication reliability and performance, adapting seamlessly to the challenges of diverse operational environments without the need for manual intervention.

[0081] In a sixth example embodiment, an inclinometer sensor is used to detect changes in the vehicle's angle of inclination, which can significantly affect antenna alignment, especially in hilly or mountainous terrain. As the vehicle ascends or descends grades, the inclinometer readings are used to trigger an adjustment in the antenna's orientation or gain. For instance, a steep incline might necessitate a lower gain setting to maintain a stable connection with a satellite or terrestrial network, as the vehicle's elevated front end could otherwise skew the direct line of sight required for effective signal transmission.

[0082] A seventh example embodiment utilizes a pressure sensor to detect changes in atmospheric pressure, which can indicate changes in altitude. As vehicles ascend to higher altitudes, atmospheric conditions can affect signal propagation, particularly in terms of air density and moisture content. When the pressure sensor detects a significant drop in atmospheric pressure, suggesting an increase in altitude, the system can switch to an antenna setting that compensates for these propagation challenges, for example increasing the gain to counteract potential signal attenuation.

[0083] In an eighth example embodiment, the vehicle utilizes an accelerometer to monitor acceleration patterns that indicate driving behaviour and environmental context, such as speeding up, slowing down, or traveling on uneven terrain. The system can use these cues to adjust antenna gain dynamically. For instance, if the accelerometer detects frequent or sudden changes in speed, it may indicate that the vehicle is navigating through a congested urban area with potential for frequent signal obstruction. The system could then lower the antenna gain to reduce the reception of unwanted signals and interference from nearby sources, enhancing the clarity and stability of the necessary communications.

[0084] In a ninth example embodiment the system incorporates a humidity sensor to adjust the antenna settings based on the moisture content in the air, which can significantly affect radio wave propagation. High humidity can lead to increased signal attenuation, particularly at higher frequencies. If the humidity sensor detects elevated moisture levels, the system may automatically increase the gain or switch to an antenna configuration that is less susceptible to moisture-related signal degradation. This ensures that the vehicle maintains effective communication capabilities in various climatic conditions, particularly in humid or rainy environments. The disclosed embodiments can optionally fail safe to the high gain antenna.

[0085] Embodiments with dual elements connected by an RF switch can optionally comprise a fail-safe mechanism. This mechanism is designed to ensure that the antenna defaults to a safer, more stable state in the event of power loss or system failure. In this specific scenario, the antenna system consists of two elements: one for high gain and one for low gain, with the high-gain configuration requiring active switching to engage.

[0086] The primary element of the antenna is configured for low gain, and it operates as the default state of the antenna system. This element provides a stable, moderate range of coverage that is adequate for maintaining basic communication functions. The second element, which offers high gain, can be engaged via an RF switch to enhance the signal strength and extend the coverage range when more robust communication capabilities are needed.

[0087] The fail-safe mechanism is centred around the behaviour of the RF switch that controls the transition between the low-gain and high-gain elements. In this design, the RF switch requires power to activate and maintain the connection to the high-gain element. If the system is powered and functioning correctly, the RF switch activates upon receiving a control signal, thus connecting the high-gain element and providing a stronger signal as needed.

[0088] However, should the system lose power or if there is a failure in the control circuitry, the RF switch will fail to activate or will deactivate if it was previously engaged. This results in the switch defaulting to its unpowered state, which is configured to naturally maintain a connection to the low-gain element. Consequently, the antenna system automatically reverts to the low-gain setting.

[0089] Some embodiments may have some of the following advantages:

[0090] • The antenna gain and / or antenna radiation pattern may be changed to suit the environment and / or operational requirements (“antenna gain and / or antenna radiation pattern adaption”);

[0091] • Increased overall system efficiency by selecting a radiation pattern for specific task, which may reduce power consumption and minimise interference;

[0092] • Dynamic modification of the radiation pattern by selectively activating or deactivating specific antenna elements, which may generally allow for tailored radiation characteristics, including beam steering, null steering, and shape control; • At least one of the gain and / or radiation pattern can be changed in response to sensor, navigation or other information.

[0093] • The antenna gain and / or radiation pattern may be changed without manual and / or mechanical reconfiguration.

[0094] • Provision of a versatile solution that may support a wide range of applications, from targeted long-range communication to broad-area signal distribution;

[0095] • When a high gain antenna mounted on a fold down bracket is folded down, it may not work ideally because the signal may he sent mostly into the ground and sky, not towards the horizon. Embodiments may sense when the antenna is folded down and change to low gain to improve performance; and

[0096] • Aerodynamics and aesthetics are broadly speaking not affected.

[0097] • The gain may be frequently and automatically changed when it would be impractical to do so manually.

[0098] • The omnidirectional antennas may be used in environments where the direction of the signal is unpredictable or where wide-area coverage is necessary, examples of which include mobile communications, broadcasting, and Wi-Fi networks. Omnidirectional antennas may provide a more uniform signal strength in all horizontal directions.

[0099] Variations and / or modifications may be made to the embodiments described without departing from the spirit or ambit of the invention. For example:

[0100] • The radome may take any suitable and desired form, for example a hollow sphere.

[0101] • The electrical conduit may comprise twisted pair wire and generally take any suitable and desired form.

[0102] • The electrical conduit may not be terminated by a connector.

[0103] • The disclosed antenna arrays can take any suitable and desired form, for example noncollinear antenna arrays.

[0104] • Generally, any suitable and desired electrically operated switch can be used, examples of which include but are not limited to a semiconductor switch, a MOS FET switch, a PIN diode switch, a MEMS switch, a RF MEMS tuneable capacitor switch, an optical switch, a liquid crystal switch, a ferroelectric material switch, a varactor diode switch, and a RF relay.

[0105] • The processor may comprise one or more of, for example, a field programmable gate array, a system on a chip, a microcontroller or generally any suitable and desired processor. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. Reference to a feature disclosed herein does not mean that all embodiments must include the feature.

[0106] Prior art, if any, described herein is not to be taken as an admission that the prior art forms part of the common general knowledge in any jurisdiction.

[0107] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises" or “comprising" is used in an inclusive sense, that is to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Claims

Claims1. A changeable-gain omni-directional antenna system comprising a switch operable to change an antenna system gain.

2. A changeable-gain omni-directional antenna system defined by claim 1 comprising an antenna feed and a plurality of antennae of different antenna gains, wherein the switch is operable to electrically-connect a selected one of the plurality of antennae of different gains to the antenna feed.

3. A changeable-gain omni-directional antenna system defined by claim 2 wherein the plurality of antennae of different antenna gains comprises at least one antenna array.

4. A changeable-gain omni-directional antenna system defined by claim 2 wherein the plurality of antennae of different antenna gains comprises at least one collinear antenna array.

5. A changeable-gain omni-directional antenna system defined by claim 1 comprising an antenna array, wherein the switch is operable to change the electrical configuration of the antenna array to change the antenna system gain.

6. A changeable-gain omni-directional antenna system defined by claim 5, wherein the antenna array comprises a plurality of antenna array elements, wherein the switch is operable to electrically connect at least one antenna element of the plurality of antenna elements to the antenna feed.

7. A changeable-gain omnidirectional antenna system defined by claim 6, wherein the switch is operable to electrically disconnect the at least one antenna element from the antenna feed.

8. A changeable-gain omnidirectional antenna system defined by any one of the claims 5 to 7, wherein the antenna array comprises a collinear antenna array.

9. A changeable-gain omni-directional antenna system defined by any one of the preceding claims wherein the switch comprises a sensor switch.

10. A changeable-gain omni-directional antenna system defined by claim 9 wherein the sensor switch comprises a tilt sensor switch.

11. A changeable-gain omni-directional antenna defined by either one of claim 9 and claim 10 wherein the sensor switch comprises at least one of an inertial measurement sensor (IMU) switch, gyroscope sensor switch, accelerometer sensor switch, magnetometer sensor switch, inclinometer sensor switch, attitude and heading reference system (AHRS) sensor switch, compass sensor switch, inertial navigation system sensor switch, proximity sensor switch, pressure sensor switch, temperature sensor switch, light sensor switch, humidity sensor switch, touch sensor switch, sound sensor switch and motion sensor switch.

12. A changeable-gain omni-directional antenna system defined by any one of the preceding claims wherein the switch comprises a manually operable switch.

13. A changeable-gain omni-directional antenna system defined by any one of the preceding claims wherein the switch comprises an electrically operable switch.

14. A changeable-gain omni-directional antenna system defined by any one of the preceding claims comprising a processor in communication with the switch and operable to change the state of the switch.

15. A changeable-gain omni-directional antenna system defined by claim 14 wherein the processor is configured to receive information and be triggered by the information to electrically operate the electrically operable switch.

16. A changeable-gain omni-directional antenna system defined by claim 15 wherein the information comprises information generated by a sensor.

17. A changeable-gain omni-directional antenna system defined by either one of claim 15 and claim 16 wherein the information comprises one or more of location information, inclination information, compass information, radio communication network information, and weather information.

18. A changeable-gain omni-directional antenna system defined by any one of the claims 15 to 17 wherein the information is received from another processor.

19. A changeable-gain omni-directional antenna system defined by any one of the preceding claims comprising a housing defining a cavity.

20. A changeable-gain omni-directional antenna system defined by claim 19 wherein the housing has a fin configuration.

21. A changeable-gain omni-directional antenna system defined by any one of the claims 1 to 19 comprising a whip.

22. A changeable-gain omni-directional antenna system defined by any one of the preceding claims configured for at least one of a CB band, a UHF band, a VHF band, a LMR band, a LTE band, a HaLow band, and a band within 380 MHz - 3500 MHz.

23. A changeable-gain omni-directional antenna system defined by any one of the preceding claims comprising a wireless network antenna.

24. A changeable-gain omni-directional antenna system defined by any one of the preceding claims comprising a GNSS antenna.

25. A changeable-gain omni-directional antenna system defined by any one of the preceding claims comprising a plurality of half-wavelength monopole antenna elements.

26. A changeable-gain omni-directional antenna system defined by any one of the preceding claims comprising at least one of a delay line, a phasing trace and a phasing coil.

27. A method for controlling an antenna system gain of a changeable-gain omni-directional antenna system, the method comprising: determining that an antenna system gain is to be changed; and operating a switch operable to change the antenna system gain.

28. A method defined by claim 27 wherein determining that the antenna gain is the be changed comprises a processor determining that the antenna gain is to be changed.

29. A method defined by either one of claim 27 and claim 28 wherein the omni-directional changeable-gain antenna is defined by any one of the claims 1 to 26.

30. Non-transitory processor readable tangible media including program instructions which when executed by a processor causes the processor to perform a method defined by any one of the claims 27-29.

31. Computer program for instructing a processor, which when executed by the processor causes the processor to perform a method defined by any one of the claims 27-29.

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