Adaptive blanker unit

Abstract

The presently disclosed subject matter relates to a Radio-Frequency (RF) receiver, capable of being mounted on a platform, configured to interact with an on-board blanker unit and at least one on-board transmitting system incapable of interacting with the on-board blanker unit, the RF receiver is associated with a processing circuitry configured to: receive, from the at least one on-board transmitting system, at least one RF signal; analyze the received RF signal so as to generate at least one input pulse signal appropriate to be received by the on-board blanker unit; and, provide the generated input pulse signal to the on-board blanker unit, thus forming interaction between the at least one on-board transmitting system and the on-board blanker unit.

Description

[0001] ADAPTIVE BLANKER UNIT

[0002] TECHNICAL FIELD

[0003] The present invention relates to the field of interference prevention, and more particularly, to the field of interference blanking units.

[0004] BACKGROUND

[0005] By definition, blanker units, also known as interference blanking units (IBUs), are systems intended to be mounted on platforms with multiple systems so as to prevent potential interferences between said systems, mainly when operating in close proximity and / or on closely spaced frequencies.

[0006] During its operation, a blanker unit accepts pulse input signals from one or more data transmitting systems, and generates and distributes blanking suppression pulse output signals to potentially affected systems so as to prevent them from reacting to said transmitting systems.

[0007] Despite their widespread use, blanker units are limited to operating solely with systems adapted to interact with them. Consequently, systems without the ability to interact with blanker units must employ insufficient and / or time-consuming solutions, such as undergoing software updates or implementing mechanisms that function a priori, which are not optimal.

[0008] Considering the above, there is a need in the art for an adaptive blanker unit capable of settling the above drawbacks.

[0009] GENERAL DESCRIPTION

[0010] In accordance with a first aspect of the presently disclosed subject matter, there is provided a Radio-Frequency (RF) receiver, capable of being mounted on a platform, configured to interact with an on-board blanker unit and at least one on-board transmitting system incapable of interacting with said on-board blanker unit, the RF receiver is associated with a processing circuitry configured to: receive, from said at least one onboard transmitting system, at least one RF signal; analyze said received RF signal so as to generate at least one input pulse signal appropriate to be received by said on-board blanker unit; and, provide said generated input pulse signal to said on-board blanker unit, thus forming interaction between said at least one on-board transmitting system and said on-board blanker unit.

[0011] In some cases, in addition to providing said generated input pulse signal, said receiver is configured to provide information relating to data transmission performed by said on-board transmitting system, over a communication channel.

[0012] In some cases, the information includes at least one of: a frequency at which the data is transmitted, a duration at which the data is transmitted, a bandwidth at which the data is transmitted, a modulation at which the data is transmitted, or a power at which the data is transmitted.

[0013] In some cases, the at least one on-board transmitting system is one of: an Electronic Warfare (EW) system, a radar system, a communication system, or a navigation system.

[0014] In some cases, the platform is either a mobile or stationary platform.

[0015] In some cases, the mobile platform is one of: an aerial platform, a ground platform, or a naval platform.

[0016] In some cases, the on-board blanker unit is in interaction with one or more additional on-board transmitting systems, such that upon said generated input pulse signal is being provided to said blanker unit, said blanker unit is configured to transmit to at least some of said additional on-board transmitting systems output pulse signals notifying said systems that said at least one on-board transmitting system is currently transmitting data.

[0017] In some cases, the one or more additional on-board transmitting systems includes at least one of: an Electronic Warfare (EW) system, a radar system, a communication system, or a navigation system.

[0018] In some cases, the receiver in a wideband receiver.

[0019] In some cases, the at least one RF signal is received over-the-air.

[0020] In some cases, the analyze step involves at least one of: (i) generating transmission envelope from said RF signal, or (ii) sampling the RF signal and measuring the momentary transmission frequency.

[0021] In accordance with a second aspect of the presently disclosed subject matter, there is provided a Radio-Frequency (RF) receiver, mounted on a platform, configured to interact with one or more on-board transmitting systems mounted on said platform, the RF receiver is associated with a processing circuitry configured to: receive at least one RF signal from at least one on-board system of said on-board systems, currently transmitting data; analyze said received RF signal so as to generate one or more notification signals directed to notify that said at least one on-board system is currently transmitting data; and, provide said one or more notification signals to one or more of the remaining on-board systems of said on-board systems so as to prevent them from responding to said at least one on-board system's data transmission.

[0022] In some cases, in addition to providing said one or more notification signals, said receiver is configured to provide said remaining on-board systems with information relating to the data transmission performed by said at least one on-board system, over a communication channel.

[0023] In some cases, the information includes at least one of: a frequency at which the data is transmitted, a duration at which the data is transmitted, a bandwidth at which the data is transmitted, a modulation at which the data is transmitted, or a power at which the data is transmitted.

[0024] In some cases, the at least one RF signal is received over-the-air.

[0025] In some cases, the receiver in a wideband receiver.

[0026] In some cases, the analyze step involves at least one of: (i) generating transmission envelope from said RF signal, or (ii) sampling the RF signal and measuring the momentary transmission frequency.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to understand the presently disclosed subject matter and to see how it may be carried out in practice, the subj ect matter will now be described, by way of non-limiting examples only, with reference to the accompanying drawings, in which:

[0029] Fig- 1 is a schematic illustration of an environment in which an exemplary adaptive blanker unit, in accordance with the presently disclosed subject matter, operates;

[0030] Fig. 2A and 2B are schematic illustrations of exemplary adaptive blanker units, in accordance with the presently disclosed subject matter;

[0031] Fig- 3 is a block diagram schematically illustrating one example of components of an exemplary adaptive blanker unit, in accordance with the presently disclosed subject matter; Fig. 4 is a flowchart illustrating an example of a sequence of operations carried out by an exemplary adaptive blanker unit, in accordance with the presently disclosed subject matter; and,

[0032] Fig- 5 is a flowchart illustrating another example of a sequence of operations carried out by an adaptive blanker unit, in accordance with the presently disclosed subject matter.

[0033] DETAILED DESCRIPTION

[0034] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the presently disclosed subject matter. However, it will be understood by those skilled in the art that the presently disclosed subject matter may be practiced without these specific details. In other instances, well- known methods, procedures, and components have not been described in detail so as not to obscure the presently disclosed subject matter.

[0035] In the drawings and descriptions set forth, identical reference numerals indicate those components that are common to different embodiments or configurations.

[0036] Unless specifically stated otherwise, as apparent from the following discussions, it is appreciated that throughout the specification discussions utilizing terms such as “receiving”, “analyzing”, “providing”, “generating”, “sampling”, or the like, include action and / or processes of a computer that manipulate and / or transform data into other data, said data represented as physical quantities, e.g., such as electronic quantities, and / or said data representing the physical objects. The terms “computer”, “processor”, “processing resource”, “processing circuitry”, and “controller” should be expansively construed to cover any kind of electronic device with data processing capabilities, including, by way of non-limiting example, a personal desktop / laptop computer, a server, a computing system, a communication device, a smartphone, a tablet computer, a smart television, a processor (e.g. digital signal processor (DSP), a microcontroller, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), etc.), a group of multiple physical machines sharing performance of various tasks, virtual servers co-residing on a single physical machine, any other electronic computing device, and / or any combination thereof.

[0037] The operations in accordance with the teachings herein may be performed by a computer specially constructed for the desired purposes or by a general-purpose computer specially configured for the desired purpose by a computer program stored in a non- transitory computer readable storage medium. The term "non-transitory" is used herein to exclude transitory, propagating signals, but to otherwise include any volatile or nonvolatile computer memory technology suitable to the application.

[0038] As used herein, the phrase "for example," "such as", "for instance" and variants thereof describe non-limiting embodiments of the presently disclosed subject matter. Reference in the specification to "one case", "some cases", "other cases" or variants thereof means that a particular feature, structure or characteristic described in connection with the embodiment s) is included in a least one embodiment of the presently disclosed subject matter. Thus, the appearance of the phrase "one case", "some cases", "other cases" or variants thereof does not necessarily refer to the same embodiment s).

[0039] It is appreciated that, unless specifically stated otherwise, certain features of the presently disclosed subject matter, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the presently disclosed subject matter, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

[0040] In embodiments of the presently disclosed subject matter, fewer, more and / or different stages than those shown in Figs. 4 and 5 may be executed. In embodiments of the presently disclosed subject matter one or more stages illustrated in Figs. 4 and 5 may be executed in a different order and / or one or more groups of stages may be executed simultaneously. Figs. 1 and 2A to 2B illustrate a general schematic of the system architecture in accordance with an embodiment of the presently disclosed subject matter. Each module in Fig. 3 may be made up of any combination of software, hardware and / or firmware that performs the functions as defined and explained herein. The modules in Fig. 3 may be centralized in one location or dispersed over more than one location. In other embodiments of the presently disclosed subject matter, the system may comprise fewer, more, and / or different modules than those shown in Fig. 3.

[0041] Any reference in the specification to a method should be applied mutatis mutandis to a system capable of executing the method and should be applied mutatis mutandis to a non-transitory computer readable medium that stores instructions that once executed by a computer result in the execution of the method. Any reference in the specification to a system should be applied mutatis mutandis to a method that may be executed by the system and should be applied mutatis mutandis to a non-transitory computer readable medium that stores instructions that may be executed by the system.

[0042] Any reference in the specification to a non-transitory computer readable medium should be applied mutatis mutandis to a system capable of executing the instructions stored in the non-transitory computer readable medium and should be applied mutatis mutandis to method that may be executed by a computer that reads the instructions stored in the non-transitory computer readable medium.

[0043] Any reference in the specification to the term “blanker unit“ or "on-board blanker unit" should be interpreted as referring to any one of: an interference blanker unit, an interference blanking unit, a programmable interference blanker unit, a programmable interference blanking unit, or any other term known in the art for providing prioritized blanking of RF transmitters and receivers to avoid mutual interference.

[0044] Bearing this in mind, attention is drawn to Fig. 1, showing a schematic illustration of an environment in which an adaptive blanker unit, in accordance with the presently disclosed subject matter, operates.

[0045] As shown in the schematic illustration, environment 100 includes a platform, denoted 102, either stationary (e.g., a building, and the like) or mobile (e.g., an aerial platform (for example, a plane, a helicopter, etc.), a ground platform (for example, a vehicle), a naval platform (for example, a vessel, etc.), and the like), containing (a) one or more on-board systems (e.g., transmitting and / or receiving systems, such as an Electronic Warfare (EW) system, a radar system, a communication system, a navigation system, etc.), denoted 102a to 102n ('n' representing any arbitrary number of on-board systems), dispersed thereon, and (b) an on-board blanker unit, denoted 104, mounted thereon, designed to prevent potential interferences between at least some of said onboard systems.

[0046] During data transmission by at least one transmitting system of on-board systems 102a to 102n, on-board blanker unit 104 is configured to receive one or more pulse input signals from said transmitting system, and generate and distribute blanking suppression pulse output signals to potentially affected on-board systems so as to prevent them from reacting to said data transmission. By way of a non-limiting example, as illustrated in Fig 1, during data transmission by on-board system 102a, represented by broken line 106, one or more pulse input signals, represented by arrow 108a, are transmitted to said on-board blanker unit 104. Upon receival of said pulse input signals, on-board blanker unit 104 generates and distributes blanking suppression pulse output signals, represented by arrows 110a to 110c, to onboard systems 102b to 102n so as to prevent them from reacting to said data transmission.

[0047] In some cases, the potentially affected on-board systems may be systems operating in close proximity to said transmitting system. In other cases, alternatively or additionally to the above, the potentially affected on-board systems may be systems operative at identical or similar frequencies to the transmitting system.

[0048] Among on-board systems 102a to 102n, at least one transmitting system may be unable of interacting with said on-board blanker unit. This incapability may arise, for example, from said transmitting system's incompetence in providing blanker unit 104 with pulse input signals during data transmission (due to, for example, software limitations, hardware limitations, and the like).

[0049] It is to be of note that the failure of said transmitting system to provide pulse input signals to said blanker unit, described above, serves as a mere example of a transmitting system's inability to interact with a blanker unit, and that other reasons may also be applicable.

[0050] By way of a non -limiting example, of on-board systems 102a to 102n, on-board system 102n may be unable of interacting with on-board blanker unit 104, due to a lack of a suitable connection, since the manufacturer of said on-board system designed it to operate on platforms without blanker units mounted thereon.

[0051] In order to overcome said transmitting system's inability to interact with on-board blanker unit 104 and maintain the ability to prevent potential interferences between said on-board systems, an adaptive blanker unit, denoted 112, was developed.

[0052] Adaptive blanker unit 112 may include at least one Radio-Frequency (RF) receiver (among other components mentioned in detail below in relation to Fig. 3), denoted 114, configured to enable receiving at least one RF signal from one or more transmitting systems unable of facilitating an interaction with said on-board blanker unit.

[0053] In some case, as illustrated in Fig. 2A, adaptive blanker unit 112 may include a single RF receiver directed to interact with a plurality of on-board transmitting systems unable of facilitating an interaction with said on-board blanker unit (either concurrently or separately). In other cases, as illustrated in Fig. 2B, adaptive blanker unit 112 may include a plurality of RF receivers, denoted 114a to 114n ('n' representing any arbitrary number of RF receivers), each directed to interact with at least one respective on-board transmitting system of said on-board transmitting systems unable of facilitating an interaction with said on-board blanker unit.

[0054] In one example, as explained in further detail below in relation to Fig. 4, adaptive blanker unit 112 may act as an adaptor directed to facilitate an interaction between said one or more transmitting systems and said on-board blanker unit, utilizing said received RF signal(s).

[0055] In another example, as explained in further detail below in relation to Fig. 5, instead of acting as an adaptor, adaptive blanker unit 112 may replace platform's 102 need for on-board blanker unit 104, as it may fulfill the same purpose (while eliminating the possibility of having an on-board system incapable of informing other on-board systems of its data transmission).

[0056] Attention is now drawn to additional components of the adaptive blanker unit 112.

[0057] Fig- 3 is a block diagram schematically illustrating one example of adaptive blanker unit 112, in accordance with the presently disclosed subject matter.

[0058] In accordance with the presently disclosed subject matter, adaptive blanker unit 112 may comprise a network interface 306. The network interface 306 (e.g., a network card, a Wi-Fi client, 3G / 4G client, or any other component), may enable adaptive blanker unit 112 to communicate over a network with external systems and handles inbound and outbound communications from such systems.

[0059] Adaptive blanker unit 112 may further comprise or be otherwise associated with a data repository 304 (e.g., a database, a storage system, a memory including Read Only Memory - ROM, Random Access Memory - RAM, or any other type of memory, etc.) configured to store data. Some examples of data that may be stored in the data repository 304 include:

[0060] • One or more received RF signals;

[0061] • One or more input pulse signals appropriate to be received by an on-board blanker unit;

[0062] • information relating to data transmission performed by one or more onboard transmitting systems; • One or more output pulse signals appropriate to be received one or more on-board systems;

[0063] • One or more transmission envelopes generated from one or more received RF signals;

[0064] • One or more RF samples of one or more received signals, etc.

[0065] Data repository 304 may be further configured to enable retrieval and / or update and / or deletion of the stored data. It is to be noted that in some cases, data repository 304 may be distributed, while the adaptive blanker unit 112 has access to the information stored thereon, e.g., via a wired or wireless network to which adaptive blanker unit 112 is able to connect (utilizing its network interface 306).

[0066] Adaptive blanker unit 112 further comprises processing circuitry 302. Processing circuitry 302 may be one or more processing units (e.g., central processing units), microprocessors, microcontrollers (e.g., microcontroller units (MCUs)) or any other computing devices or modules, including multiple and / or parallel and / or distributed processing units, which are adapted to independently or cooperatively process data for controlling relevant adaptive blanker unit 112 resources and for enabling operations related to adaptive blanker unit’s 112 resources.

[0067] The processing circuitry 302 comprises (i) an interaction module 308, configured to perform an interaction process, as further detailed herein, inter alia with reference to Fig. 4, and (ii) an interference prevention module 310, configured to perform interference prevention process, as further detailed herein, inter alia with reference to Fig. 5.

[0068] Turning to Fig. 4 there is shown a flowchart illustrating one example of operations carried out by the adaptive blanker unit 112, in accordance with the presently disclosed subject matter.

[0069] As mentioned hereinbefore, adaptive blanker unit 112 may be utilized to settle the inability of one or more on-board transmitting systems to interact with an on-board blanker unit, by serving as an adaptor directed to facilitate an interaction between them.

[0070] Accordingly, the adaptive blanker unit 112 may be configured to perform an interaction process 400, e.g., using interaction module 308.

[0071] For this purpose, adaptive blanker unit 112 receives, through its RF receiver 114, at least one RF signal from at least one on-board transmitting system unable of facilitating an interaction with on-board blanker unit 104 (block 402). Upon receival, adaptive blanker unit 112 analyzes the received RF signal so as to generate at least one input pulse signal appropriate to be received by on-board blanker unit 104 (block 404), and provide the generated input pulse signal to said on-board blanker unit, thus forming interaction between said at least one on-board transmitting system and said on-board blanker unit (block 406).

[0072] In some cases, the at least one RF signal may be received, for example, over-the- air.

[0073] In some cases, in addition to providing said generated input pulse signal, adaptive blanker unit 112 may be configured to provide information relating to the data transmission performed by the on-board transmitting system (e.g., a frequency at which the data is transmitted, a duration at which the data is transmitted, a bandwidth at which the data is transmitted, a modulation at which the data is transmitted, a power at which the data is transmitted, etc.). In such cases, said information may be provided, for example, over a communication channel or a data bus.

[0074] In some cases, upon providing said generated input pulse signal to said on-board blanker unit, said blanker unit is configured to transmit to one or more on-board systems with which it is capable of interacting, one or more output pulse signals notifying said systems that said at least one on-board transmitting system is currently transmitting data.

[0075] In some cases, said analyze step may involve, for example, at least one of: (i) generating transmission envelope from said RF signal, or (ii) sampling the RF signal and measuring the momentary transmission frequency.

[0076] It is to be of note that the above serve as mere examples and the other types of actions, alternatively or additionally, may also be applicable.

[0077] Turning to Fig. 5 there is shown a flowchart illustrating another example of operations carried out by the adaptive blanker unit 112, in accordance with the presently disclosed subject matter.

[0078] As mentioned hereinbefore, adaptive blanker unit 112 may be designed to fulfill the same purpose as an on-board blanker unit, thereby eliminating the need for a blanker unit.

[0079] Accordingly, the adaptive blanker unit 112 may be configured to perform an interference prevention process 500, e.g., using interference prevention module 310. For this purpose, adaptive blanker unit 112 receives at least one RF signal, through its RF receiver 106, from at least one on-board system of said on-board systems, currently transmitting data (block 502).

[0080] Upon receival, adaptive blanker unit 112 analyzes said received RF signal so as to generate one or more notification signals directed to notify that said at least one onboard system is currently transmitting data (block 504).

[0081] Once generated, the one or more notification signals are provided to one or more of the remaining on-board systems of said on-board systems so as to prevent them from responding to said at least one on-board system's data transmission (block 506).

[0082] In some cases, the at least one RF signal may be received, for example, over-the- air.

[0083] In some cases, in addition to providing said generated input pulse signal, adaptive blanker unit 112 may be configured to provide information relating to the data transmission performed by the on-board transmitting system (e.g., a frequency at which the data is transmitted, a duration at which the data is transmitted, a bandwidth at which the data is transmitted, a modulation at which the data is transmitted, a power at which the data is transmitted, etc.). In such cases, said information may be provided, for example, over a communication channel or a data bus.

[0084] In some cases, said analyze step may involve, for example, at least one of: (i) generating transmission envelope from said RF signal, or (ii) sampling the RF signal and measuring the momentary transmission frequency.

[0085] It is to be of note that the above serve as mere examples and the other types of actions, alternatively or additionally, may also be applicable.

[0086] It is to be noted, with reference to Figs. 4 and 5, that some of the blocks may be integrated into a consolidated block or may be broken down to a few blocks and / or other blocks may be added. It is to be further noted that some of the blocks are optional. It should be also noted that whilst the flow diagram is described also with reference to the system elements that realizes them, this is by no means binding, and the blocks may be performed by elements other than those described herein.

[0087] It is to be understood that the presently disclosed subject matter is not limited in its application to the details set forth in the description contained herein or illustrated in the drawings. The presently disclosed subject matter is capable of other embodiments and of being practiced and carried out in various ways. Hence, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for designing other structures, methods, and systems for carrying out the several purposes of the present presently disclosed subject matter.

[0088] It will also be understood that the system according to the presently disclosed subject matter may be implemented, at least partly, as a suitably programmed computer. Likewise, the presently disclosed subject matter contemplates a computer program being readable by a computer for executing the disclosed method. The presently disclosed subject matter further contemplates a machine-readable memory tangibly embodying a program of instructions executable by the machine for executing the disclosed method.

Claims

CLAIMS:

1. A Radio-Frequency (RF) receiver, mounted on a platform, configured to interact with one or more on-board transmitting systems mounted on said platform, the RF receiver is associated with a processing circuitry configured to: receive at least one RF signal from at least one on-board system of said on-board systems, currently transmitting data; analyze said received RF signal so as to generate one or more notification signals directed to notify that said at least one on-board system is currently transmitting data; and, provide said one or more notification signals to one or more of the remaining on-board systems of said on-board systems so as to prevent them from responding to said at least one on-board system's data transmission.

2. The RF receiver of claim 1, wherein, in addition to providing said one or more notification signals, said receiver is configured to provide said remaining onboard systems with information relating to the data transmission performed by said at least one on-board system, over a communication channel.

3. The RF receiver of claim 2, wherein said information includes at least one of: a frequency at which the data is transmitted, a duration at which the data is transmitted, a bandwidth at which the data is transmitted, a modulation at which the data is transmitted, or a power at which the data is transmitted.

4. The RF receiver of claim 1, wherein said at least one RF signal is received over- the-air.

5. The RF receiver of claim 1, wherein said receiver in a wideband receiver.

6. The RF receiver of claim 1, wherein said analyze step involves at least one of: (i) generating transmission envelope from said RF signal, or (ii) sampling the RF signal and measuring the momentary transmission frequency.

7. A Radio-Frequency (RF) receiver, capable of being mounted on a platform, configured to interact with an on-board blanker unit and at least one on-board transmitting system incapable of interacting with said on-board blanker unit, the RF receiver is associated with a processing circuitry configured to: receive, from said at least one on-board transmitting system, at least one RF signal; analyze said received RF signal so as to generate at least one input pulse signal appropriate to be received by said on-board blanker unit; and, provide said generated input pulse signal to said on-board blanker unit, thus forming interaction between said at least one on-board transmitting system and said on-board blanker unit.

8. The RF receiver of claim 7, wherein, in addition to providing said generated input pulse signal, said receiver is configured to provide information relating to data transmission performed by said on-board transmitting system, over a communication channel.

9. The RF receiver of claim 8, wherein said information includes at least one of: a frequency at which the data is transmitted, a duration at which the data is transmitted, a bandwidth at which the data is transmitted, a modulation at which the data is transmitted, or a power at which the data is transmitted.

10. The RF receiver of claim 7, wherein said at least one on-board transmitting system is one of: an Electronic Warfare (EW) system, a radar system, a communication system, or a navigation system.

11. The RF receiver of claim 7, wherein said platform is either a mobile or stationary platform.

12. The RF receiver of claim 11, wherein said mobile platform is one of: an aerial platform, a ground platform, or a naval platform.

13. The RF receiver of claim 7, wherein said on-board blanker unit is in interaction with one or more additional on-board transmitting systems, such that upon said generated input pulse signal is being provided to said blanker unit, said blanker unit is configured to transmit to at least some of said additional on-board transmitting systems output pulse signals notifying said systems that said at least one on-board transmitting system is currently transmitting data.

14. The RF receiver of claim 13, wherein said one or more additional on-board transmitting systems includes at least one of: an Electronic Warfare (EW) system, a radar system, a communication system, or a navigation system.

15. The RF receiver of claim 7, wherein said receiver in a wideband receiver.

16. The RF receiver of claim 7, wherein said at least one RF signal is received over- the-air.

17. The RF receiver of claim 7, wherein said analyze step involves at least one of: (i) generating transmission envelope from said RF signal, or (ii) sampling the RF signal and measuring the momentary transmission frequency.

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