Assignment of channels for communicating with an unmanned vehicle

An embodiment of a radio for disposition on an unmanned vehicle includes first and second receiver circuits. The first receiver circuit is configured to receive a signal over a current active channel within a frequency sub band corresponding to the unmanned vehicle. And the second receiver circuit is configured to monitor a respective availability and a respective quality of each of a current standby channel and at least one other channel within the frequency sub band while the first receiver circuit is receiving the signal, and to request an assignment of one of the at least one other channel as a new standby channel if the second receiver circuit determines that the quality of the one of the at least one other channel is better than the quality of the current standby channel.

SUMMARY

FIG. 1is a diagram of an unmanned-aircraft system10, which includes an unmanned aircraft12having an airborne radio14(the radio is called an “airborne” radio even while the unmanned aircraft is grounded), a pilot-in-control (PIC) radio16, one or more ground radio systems (GRS)18, and a communication-assignment server20.

The unmanned aircraft12is, for example, a military, or other type of, drone.

The airborne and PIC radios14and16are configured to communicate with one another over a selectable active wireless channel22so that a pilot (not shown inFIG. 1), who is remote from the unmanned aircraft12, can maneuver, and otherwise control the operation of, the unmanned aircraft.

Each GRS18is configured to communicate with the airborne radio14over a respective selectable active wireless channel24, and is configured to communicate with the PIC radio16via a communication link26such as a public-switched telephone network (PSTN), a mobile network, the internet, or an internet-based network (e.g., the cloud). Furthermore, each GRS18typically is configured to allow communication between the airborne radio14and the PIC radio16via the active wireless channel24only while the airborne radio is too far from the PIC radio to communicate with the PIC radio over the active channel22.

And the communication-assignment server20(e.g., a hardware server on the cloud) is configured to communicate with the PIC radio16via a communication link28, which can be the same as, or different from, the communication link26. Examples of the communication link28include a (PSTN), a mobile network, the internet, or an internet-based network (e.g., the cloud).

The airborne radio14, the PIC radio16, the one or more GRSs18, and the links26and28over which the airborne radio, the PIC radio, and the one or more GRSs communicate, can form, or can be part of, a Control and Non-Payload Communications (CNPC) Link System. In the configuration described in conjunction withFIG. 1, the system10can be configured as a typical CNPC terrestrial application that complies with the Radio Technical Commission for Aeronautics (RTCA) DO-362 Standard. According to the RTCA DO-362 Standard, communications over the active wireless channels22and24can be in the L frequency band (1040-1050 MHz) or in the C frequency band (5030-5090 MHz).

Still referring toFIG. 1, before the unmanned aircraft12takes off, the pilot (not shown inFIG. 1) sends to the assignment server20, via the PIC radio16and the communication link28, a request for an assignment of a frequency band, and of a sub band within the frequency band, for the active channel22.

The assignment server20assigns, to the airborne and PIC radios14and16, a frequency band (e.g., L band, C band) and a sub band within the frequency band, and notifies the PIC radio, via the communication link28, of the frequency-band and sub-band assignment. The assignment server20is configured to track the use of the frequency bands and sub bands for which it has assignment control. For example, the assignment server20typically is configured to track the frequency-band and sub-band assignments for multiple unmanned aircraft or other unmanned vehicles in the same geographical region as the unmanned aircraft12.

The pilot then selects, within the assigned sub band, an active frequency (heretofore and hereinafter “active channel”) and a standby frequency (hereinafter “standby channel”) over which the airborne and PIC radios14and16can communicate. The assigned sub band can include, for example, approximately five to fifty frequency slots (hereinafter “channels”).

The pilot can select the active channel22and a standby channel by using the PIC radio16to determine the quality of each available channel within the assigned sub band, and by selecting the two channels having the highest qualities. In a detailed example, the pilot operates the PIC radio16to send one or more test signals to the airborne radio14over each available channel in the sub band (an “available channel” is a channel that the airborne and PIC radios are configured to use, and that the assignment server20has not identified to the PIC radio as “unavailable”). For each available channel, the airborne radio14determines respective channel-quality metrics such as the strength of the received signal (i.e., a measure of the level of attenuation that the channel imparts to the signal), the level of distortion in the received signal, the loss of information from packets carried by the received signal (if the received signal includes data packets and the airborne radio has a priori “knowledge” of the content of the data packets), the level of jamming of the received signal, the level of interference experienced by the received signal, and the level of noise received over the channel. The airborne radio14then sends, to the PIC radio16, the determined channel-quality metrics, or combines the metrics into a quality “score” and then sends, to the PIC radio, the score, possibly along with the determined metrics; alternatively, the PIC radio can be configured to determine the score from the channel-quality metrics provided by the airborne radio. The PIC radio16displays, or otherwise communicates, the determined quality metrics, the score, or both the metrics and the score, to the pilot, who determines the two “best” channels in response to the displayed quality metrics or quality score for each channel, and decides which of the best channels to use for the active channel, and which to use for the standby channel. For example, the pilot can select the channel with the best overall quality as the active channel, and can select the channel with the second-best overall quality as the standby channel.

The pilot then sends to the assignment server20, via the PIC radio16and the communication link28, a request for assignment of the selected active and standby channels. If these channels are still unused, i.e., are still available, then the assignment server20assigns the requested channels to the airborne and PIC radios14and16. If at least one of the requested channels is being used, then the assignment server20notifies the PIC radio16via the link28, and the pilot repeats the above-described procedure until he/she selects two channels of sufficient quality that are available for assignment.

The pilot also can send, to the assignment server20, a “blind” request for assignment of an active channel and a standby channel for each GRS18that covers a geographic region through which the pilot anticipates the unmanned aircraft12will fly. This request is “blind” because, due to the GRS18being out of range of the airborne radio14, the pilot cannot test the requested active and standby channels ahead of time. That is, the pilot selects the active and standby channels for each GRS18in a random fashion, or guesses, based on experience or other factors, which channels are likely to have the highest qualities. Of course if a GRS18is within range of the airborne radio14at the time of the channel-assignment request, then the pilot can test the channels ahead of time using a procedure similar to that described above for the selection of the active and standby channels between the airborne radio and the PIC radio16.

Next, using the PIC radio16to communicate with the unmanned aircraft12via the airborne radio14, the pilot controls the unmanned aircraft12to take off. For example, the PIC radio16can include a joystick, or another interface, that allows the pilot to maneuver, and to otherwise control, the unmanned aircraft12. Furthermore, the airborne radio14is configured to receive, and possibly to demodulate and to decode, signals received from the PIC radio16, and to provide the received signals to circuitry of a control and navigation system (not shown inFIG. 1) on board the unmanned aircraft12. In response to the received signals (as may be processed by the airborne radio), the control and navigation system maneuvers, and otherwise controls, the unmanned aircraft12as commanded by the pilot. For example, in addition to being configured to maneuver the aircraft12by moving the rudder, flaps, and ailerons, the control and navigation system can be configured to adjust the aircraft's speed by adjusting, e.g., engine thrust.

After the unmanned aircraft12takes off, the pilot flies the aircraft by continuing to maneuver, and otherwise to control, the aircraft via the PIC radio16and the airborne radio14. For example, the pilot can maneuver the aircraft12to complete a mission, such as to travel to, and to target with a weapon, one or more targets. In this example, the aircraft12can also include one or more weapons systems (e.g., gun, missile launcher, laser, not shown inFIG. 1) that are configured for pilot control via the PIC radio16and the airborne radio14.

While the pilot is remotely flying the unmanned aircraft12, he/she monitors, via the PIC radio16, the quality of the previously requested and assigned active wireless channel22(which channel is used for communication depends on the range of the aircraft from the PIC radio as described above). For example, the airborne radio14can continue to determine, and send to the PIC radio16, the above-described quality metrics or quality score for the active channel22. Or, the pilot can detect a drop in the quality of the active channel if, for example, the aircraft12is slow to respond, or fails to respond, to a maneuver or other command. For example, the pilot can determine such a slow response or a failure to respond, by viewing, on the PIC radio16or on another display, the flight path of the aircraft in real time, or video from a camera on board the aircraft12.

If the pilot determines that the quality of the active channel22is so poor (e.g., at least one of the quality metrics or quality score falls below a respective threshold) that the active channel is unsuitable for piloting the unmanned aircraft12, then he/she can cause the airborne radio14and the PIC radio16to “switch over” communications to the assigned standby channel, which, after the switch over, becomes the active channel22.

The pilot initiates the switch over, e.g., by flipping a switch, pushing a button, or selecting an option from a menu displayed, on the PIC radio16.

Next, the PIC radio16sends, over the currently active channel, a command to the airborne radio14to switch over to the standby channel within a predetermined time period (e.g., a few milliseconds to a few seconds); if the airborne radio does not already “know” the frequency of the standby channel, then the PIC radio also can provide this information to the airborne radio over the currently active channel.

Then, the airborne radio14acknowledges to the PIC radio16receipt of the switchover command.

Next, after the expiration of the predetermined time period, both the airborne radio14and the PIC radio16begin communicating on the former standby channel, which now becomes the current active channel22.

The pilot can perform a similar procedure if the PIC radio16is communicating with the airborne radio14via one of the GRSs18. In this case, the GRS18and the airborne radio14switch over to a standby channel that, after the switch over, becomes the new active channel24.

Unfortunately, there can be problems with the unmanned aircraft system10.

First, the need for the pilot to monitor the quality of the active channel22takes time mental concentration away from the pilot's other tasks and duties. And if the pilot is occupied with other aspects of flying the unmanned aircraft12, he/she may not notice a deterioration of the quality of the active channel22until the quality becomes too low to allow him/her to control the unmanned aircraft.

Second, a problem can arise if the quality of the standby channel is, or later becomes, too low for allowing communications with the airborne radio14.

Because after the pilot causes the standby channel to become the new active channel there is no assigned standby channel, if the quality of the new active channel is, or becomes, too low, then the pilot can switch back to the previous active channel, which, after the previous switch over, became the de facto standby channel.

But if the previous active channel (i.e., the new, de facto, standby channel) still has a quality that is too low for communication between the airborne and PIC radios14and16, the pilot's only remaining option is to perform, anew, the above-described channel-assignment-request procedure to obtain, from the assignment server20, a new active channel and a new standby channel (the pilot typically cannot select new active and standby channels without authorization from the assignment server).

The pilot's requesting and receiving an assignment of new active and standby channels can take a significant amount of time (e.g., 30 seconds to 10 minutes), and, unlike the first time that the pilot requested and obtained assigned active and standby channels (i.e., while the unmanned aircraft12was grounded), the unmanned aircraft is now airborne.

Consequently, while the pilot is testing the qualities of other channels within the sub band, and is requesting and receiving an assignment of new active and standby channels, the unmanned aircraft12may be out of the pilot's control, a condition called a “flyaway” condition. This is because the airborne radio14and the PIC radio16typically can communicate over only one channel at a time. So while the pilot is testing the qualities of other channels, he/she cannot send, and the airborne radio14cannot receive, commands to the unmanned aircraft12over the current active channel22. That is, to determine what two other channels to request as the new active and standby channels, the pilot typically must switch over the PIC radio16and airborne radio14to those channels to determine their respective levels of quality.

The unmanned aircraft12also may experience a flyaway condition when the airborne radio14switches over from the active channel22to an active channel24as the unmanned aircraft12flies out of direct communication range of the PIC radio16and into range of one or more of the GRSs18. If the quality of the new active channel24is too low, and the quality of the standby channel for the GRS18is also too low, then, as described above, the unmanned aircraft12may experience a flyaway condition while the pilot is testing the qualities of other channels within the sub band assigned to the airborne radio14and the GRS18, and is requesting and receiving an assignment of new active and standby channels.

Unfortunately, while the unmanned aircraft12is experiencing a flyaway condition, and is, therefore, out of the pilot's control, or even while the aircraft is within the pilot's control but the pilot is distracted by monitoring the quality of the active channel, the aircraft may go off course, crash, activate weapons at an inappropriate time, or experience or cause other problems.

Therefore, a need has arisen for a device, such as a radio, that is configured to monitor channels in the assigned sub band other than the active channel and to request reassignment of the standby channel to one of the other channels if the quality of the standby channel is too low, or if an unused channel has a better quality than the standby channel.

An embodiment of a radio that solves at least one of the aforementioned problems is configured for disposition on an unmanned vehicle and includes first and second receiver circuits. The first receiver circuit is configured to receive a signal over a current active channel within a frequency sub band corresponding to the unmanned vehicle. And the second receiver circuit is configured to monitor a respective availability and a respective quality of each of a current standby channel and at least one other channel within the frequency sub band while the first receiver circuit is receiving the signal, and to request an assignment of one of the at least one other channel as a new standby channel if the second receiver circuit determines that the quality of the one of the at least one other channel is better than the quality of the current standby channel.

By monitoring, for example, the quality metrics and quality scores of the other channels within the assigned frequency sub band, and by requesting reassignment of the standby channel when the quality of the current standby channel is too low to allow proper control of the unmanned vehicle, such a radio significantly reduces the chances that the quality of the standby channel will be too low after a channel switchover, and thus significantly reduces the number of, or eliminates, times during which the pilot is distracted with channel-quality monitoring, and times during which the unmanned aircraft experiences a flyaway condition.

DETAILED DESCRIPTION

Each non-zero value, quantity, or attribute herein preceded by “substantially,” “approximately,” “about,” a form or derivative thereof, or a similar term, encompasses a range that includes the value, quantity, or attribute ±20% of the value, quantity, or attribute, or a range that includes ±20% of a maximum difference from the value, quantity, or attribute. And for a zero-value, the encompassed range is ±1 of the same units unless otherwise stated.

FIG. 2is a diagram of an unmanned-aircraft system40, which includes an unmanned aircraft42having an airborne radio44with channel monitoring, according to an embodiment. InFIG. 2, like numbers reference components of the system40common to the system10ofFIG. 1. Other than including the airborne radio44and a common communication link46over which the PIC radio16, GRSs18, and communication-assignment server20can communicate with one another, the system40can be similar to the unmanned-aircraft system10ofFIG. 1. Furthermore, the communication link46can be the same as, or similar to, one of the links26and28ofFIG. 1.

In addition to being configured to communicate with the PIC radio16or a GRS18over an active wireless channel22or24, respectively, the airborne radio44is configured to monitor the quality of the standby channel, to monitor the quality of at least one of the other channels within the same sub band as the active and standby channels, and to request reassignment of the standby channel to an unassigned channel if the quality of the standby channel becomes too low to support accurate communications between the airborne radio and the PIC radio or GRS18. And the airborne radio44can also be configured to monitor the quality of the active channel and to request switching over to the standby channel if the quality of the active channel becomes too low to support accurate communications between the airborne radio and the PIC radio16or GRS18.

Still referring toFIG. 2, operation of the system40is described, according to an embodiment.

While the pilot (not shown inFIG. 2), via the PIC radio16, is sending flight commands to the airborne radio44over the active wireless channel22, the airborne radio is monitoring the assigned standby channel and at least one other channel in the assigned sub band, and is determining the respective quality levels of the standby channel and of the at least one other channel in a manner similar to that described above in conjunction withFIG. 1.

If the airborne radio44determines that the quality of the standby channel is, or becomes, too low for use as a communication channel between the airborne radio and the PIC radio16, then the airborne radio determines whether the respective quality of any of the at least one other channel is suitable to carry communications between the airborne radio and the PIC radio.

If the airborne radio44determines that the quality of one of the at least one other communication channel is suitable to carry communication signals between the airborne radio and the PIC radio16, then the airborne radio sends a request to the assignment server20, for example, via the PIC radio, to reassign the one of the at least one other communication channel as the new standby channel. The PIC radio16can be configured to automatically route this request from the airborne radio44to the assignment server20via the link46. If more than one of the at least one other communication channel have suitably high qualities, then the airborne radio sends a request to the assignment server20to reassign, as the new standby channel, the one of the at least one other communication channel having the highest quality. If the assignment server20denies the request to reassign the standby channel, because, for example, the requested other channel having the highest quality is in use by another unmanned aircraft system, then the airborne radio44can send a request to the assignment server to reassign, as the new standby channel, the one of the at least one other communication channel having the next-highest quality, and so on. If the assignment server20approves the request, then it sends, to the PIC radio16, approval of the reassignment. The PIC radio16then can send the approval of the reassignment to the airborne radio44, or the assignment server20can route the approval directly to the airborne radio via the PIC radio. In response to receiving approval of the reassigned standby channel, both the PIC radio16and the airborne radio44store the identity of the reassigned standby channel in memory circuits (not shown inFIG. 2) on board the PIC radio and the airborne radio, respectively.

By implementing the above procedure, the airborne radio44significantly increases the chances that if the PIC radio16automatically (or the pilot manually) switches over to the standby channel, then the standby channel will have a sufficient quality to carry communication signals between the PIC radio and the airborne radio. Therefore, by implementing the above procedure, the airborne radio44reduces the number of, or eliminates, times during which the unmanned aircraft42experiences a flyaway condition or during which the pilot is distracted from flying the aircraft.

The airborne radio44is configured to implement a similar procedure while it is communicating with the PIC radio16via a GRS18and an active wireless channel24. Alternatively, because the GRS18is configured to communicate with the assignment server20directly over the communication link46, the airborne radio44can bypass the PIC radio16and make the standby-channel reassignment request directly to the assignment server20via the GRS18and the link46. If the assignment server20approves the reassignment of the standby channel, then it notifies, via the link46and the GRS18, the airborne radio44, and notifies, via the link46, the PIC radio16.

Still referring toFIG. 2, operation of the system10is described according to another embodiment.

The airborne radio44monitors, determines, and tracks (e.g., stores in a memory (not shown inFIG. 2) that is part of the airborne radio or that is otherwise on board the unmanned aircraft42) the qualities of the current active channel22, the current standby channel, and the at least one other channel in the sub band.

Furthermore, the airborne radio44switches over to the standby channel, or to one of the at least one other channel in the assigned sub band, if the quality of the current active channel is, or becomes, too low to support accurate communication between the airborne radio and the PIC radio16.

If the airborne radio44determines that the quality of the currently active channel22is too low to support accurate communications between the airborne radio and the PIC radio16, then the airborne radio determines whether the quality of the standby channel is high enough to support accurate communications between the airborne radio and the PIC radio.

If the airborne radio44determines that the quality of the standby channel is high enough to support accurate communications between the airborne radio and the PIC radio16, then the airborne radio sends a request to the PIC radio to switch over to the standby channel.

In response to the request, the PIC radio16acknowledges the request to the airborne radio44, and then the airborne and PIC radios automatically switch over to the standby channel at a predetermined time that is, for example, specified in the request, i.e., without any action by the pilot. For example, the automatic switch over to the standby channel may be transparent to the pilot.

Alternatively, the PIC radio16can notify the pilot of the request, for example, via a display on the PIC radio or via other means (e.g., an audio notification), and the pilot can manually switch over to the standby channel as described above in conjunction withFIG. 1.

If, however, the airborne radio44determines that the quality of the standby channel also is too low to support accurate communications between the airborne radio and the PIC radio16, then the airborne radio sends a request to the assignment server20to reassign the active channel22to one of the at least one other channel in the sub band having a quality that is high enough to support accurate communications between the airborne radio and the PIC radio. For example, the airborne radio14can request the assignment server20to reassign the active channel22to the other channel that the airborne radio determined to have the highest quality.

If there is more than one other channel with a high-enough quality, then the airborne radio14can request the assignment server20to reassign both the current active channel22and the current standby channel to two of the other channels in the assigned sub band. For example, the airborne radio14can request the assignment server20to reassign the current active channel22and the current standby channel to the other two channels having the highest qualities (e.g., reassign the current active channel to the other channel having the highest quality, and reassign the current standby channel to the other channel having the second-highest quality).

In response to the request, if none of the requested other channels are available, then the assignment server20notifies the airborne receiver44, which repeats the above process to select another one or more of the at least one other channel for reassignment of the current active channel, and possibly for reassignment of the current standby channel.

If only one of the requested other channels are available, then the assignment server20reassigns the current active channel22to the one of the requested other channels (e.g., even if the airborne radio14requested reassignment of the standby channel to this other channel), and notifies the airborne radio44and the PIC radio16of the active-channel reassignment. If the airborne radio44also requested reassignment of the standby channel, then the assignment server20notifies the airborne radio that the second requested channel is unavailable, and the airborne receiver repeats the above-described process to request reassignment of the standby channel to another one of the other channels.

If both of the requested other channels are available, then the assignment server20respectively reassigns the current active channel22and the current standby channel to the two requested other channels, and notifies the airborne radio44and the PIC radio16of the reassignment.

After the PIC radio16acknowledges the reassignment of the current active channel22to the airborne radio14, the airborne and PIC radios switchover the current active channel to the newly assigned active channel. In a manner similar to that described above, the pilot may switchover the PIC radio16and airborne radio44to the newly assigned active channel manually via a control on the PIC radio, or the PIC and airborne radios can implement the switch over automatically without pilot action. For example, the automatic switch over to the newly assigned active channel may be transparent to the pilot.

And if the assignment server20also reassigned the current standby channel to another one of the channels in the sub band, then the PIC radio16acknowledges the request to the airborne radio44, and both the airborne and PIC radios store the identity of the reassigned standby channel in memory circuits (not shown inFIG. 2) on board the airborne radio and the PIC radio, respectively.

While the airborne radio44is communicating with the PIC radio16via a current active wireless channel24and a GRS18, the airborne radio can implement a similar procedure to request reassignment of the current active channel24, and also to request reassignment of the current standby channel, between the airborne radio and the GRS.

Still referring toFIG. 2, alternate embodiments of the system40are contemplated. For example, although described as being a wired link, the link46can be a wireless link in part or in totality. Furthermore, although described as allowing only one channel to be assigned as a standby channel at any given time, the system40can be configured to allow assignment of two or more standby channels at any given time so that if the quality of a first standby channel is too low to support accurate communications, the airborne radio44can initiate a switchover from the active channel to a second standby channel. Moreover, although the airborne radio44is described as being configured to request reassignment of the current active and standby channels, one or more of the PIC radio16and the GRSs18can be so configured instead of, or in addition to, the airborne radio44being so configured. In addition, although described as including an unmanned aircraft42, the system40can include any other type of unmanned vehicle instead of, or in addition to, the unmanned aircraft. Furthermore, in addition to determining, monitoring, and tracking the quality of a respective channel, the airborne radio44can be configured to monitor and to determine the availability of each channel other than the active and standby channels. For example, the airborne radio44can be configured to detect whether a respective other channel is being used for communications between a PIC radio or GRS and another unmanned aircraft.

FIG. 3is a diagram of the airborne radio44ofFIG. 2, according to an embodiment.

The airborne radio44includes two or more receiver circuits601-60n, a corresponding number of receive antennas621-62n, a transmitter circuit64, a transmit antenna66, and a network68(e.g., a bus, Ethernet®) over which the receiver circuits are configured to communicate with one another and with the transmitter circuit.

Each receiver circuit601-60nincludes respective receiving circuitry701-70nand respective computing circuitry721-72n.

Each receiving circuitry70can be any suitable receiving circuitry, such as a frequency-tunable super heterodyne receiver, that is configured to receive, via a respective receiving antenna62, a signal over a respective channel within the sub band assigned to the airborne radio44by the assignment server20(FIG. 2), and that is configured to process the received signal, by, e.g., performing one or more of amplifying, demodulating, and decoding the received signal. In addition to being configured to provide the processed received signal to the respective computing circuitry72, each receiving circuitry70is configured to provide the processed received signal to a navigation and control system (not shown inFIG. 3) on board the unmanned aircraft42(FIG. 2). Such a navigation and control system is configured to maneuver, and otherwise to control, the unmanned aircraft42in response to the pilot commands that the processed received signal carries. Furthermore, if the unmanned aircraft42includes one or more other systems, such as a weapons system (not shown inFIG. 3), then each receiving circuitry70is configured to provide the processed received signal to each of these other systems.

Each computing circuitry72can be any suitable computing circuitry such as a microprocessor, microcontroller, field-programmable gate array (FPGA), or other software-, firmware-, or bit-pattern configurable circuitry, that is configured to analyze the processed signal from the respective receiving circuitry70, and that is configured to determine the quality of the respective channel over which the receiving circuitry received the analyzed signal. For example, the computing circuitry72can be configured to determine, in a conventional manner, quality metrics associated with the channel, such quality metrics including, e.g., signal strength (a measure of signal attenuation imparted by the channel), the level and type of signal distortion, the level of signal jamming in the channel, the level and type of interference in the channel, and the level of noise in the channel. Further to this example, the computing circuitry72can be configured to generate, in a conventional manner, a quality score for the channel in response to one or more of the quality metrics that the computing circuitry determines for the channel.

Furthermore, a first one of the receiver circuits60is configured as an active receiver circuit for receiving signals over the ACTIVE CHANNEL22or24, a second one of the receiver circuits is configured as a main channel-monitoring receiver circuit, and third and subsequent receiver circuits re configured as auxiliary channel-monitoring receiver circuits. For example, the computing circuitry72of the main receiver circuit60can be configured to collect all of the channel-quality data from the active receiver circuit and the auxiliary receiver circuits, and to determine, for example, which of the monitored channels has the highest quality, which of the monitored channels has the second-highest quality, and so on. For purposes of example, it is assumed that the receiver circuit601is configured as the active receiver circuit for receiving signals over the ACTIVE CHANNEL22or24, the receiver circuit602is configured as the main-channel-monitoring receiver circuit, and the remaining receiver circuits603-60nare configured as auxiliary-channel-monitoring receiver circuits. It is understood, however, that the receiver circuit601could be a main or auxiliary receiver circuit, that the receiver circuit602could be an active or auxiliary receiver circuit, that any of the receiver circuits603-60ncould be an active receiver circuit or a main receiver circuit, and that the airborne radio44could include as few as two receiver circuits601and602such that the airborne radio would include no auxiliary receiver circuits.

Each of the receive antennas62can be any suitable type of receive antenna, the transmitter circuit64can be any suitable type of transmitter circuit, the transmit antenna66can be any suitable type of transmit antenna, and the network68can be any suitable type of communication network (e.g., Ethernet®).

Still referring toFIG. 3, operation of the airborne receiver44is described according to an embodiment in which the receiver circuit601is configured as the active receiver and receives a signal from either the PIC radio16or a GRS18over an ACTIVE CHANNEL22or24(FIG. 2), the receiver circuit602is configured as the main-channel-monitoring receiver circuit and monitors the STANDBY CHANNEL, and the receiver circuits603-60nare configured as the auxiliary-channel-monitoring receiver circuits and, therefore, respectively monitor the AUXILIARY CHANNELS, which are the channels in the sub band other than the current ACTIVE CHANNEL and the current STANDBY CHANNEL. For purposes of the following example, it is assumed that the active receiver circuit601receives the signal from the PIC radio16over the ACTIVE CHANNEL22, it being understood that the below-described operation of the airborne radio44and its components would be similar if the active receiver circuit were to receive the signal from a GRS18over an ACTIVE CHANNEL24.

While the receiving circuitry701of the active receiver circuit601is receiving and processing the signal from the PIC radio16via the ACTIVE CHANNEL22, and is providing the processed signal, and the pilot commands that the processed signal carriers, to a control and navigation subsystem on board the aircraft42(not shown inFIG. 3), the computing circuit721of the active receiver circuit analyzes the processed signal and determines, monitors, and tracks the quality of the ACTIVE CHANNEL22. For example, the computing circuit721may store a history of the determined quality metrics and quality score of the ACTIVE CHANNEL22in a memory (not shown) on board the receiver circuit601.

Also while the receiving circuitry701of the active receiver circuit601is receiving and processing the signal from the PIC radio16(FIG. 1), the respective receiving circuitry702-70nof each of the main and auxiliary receiver circuits602-60nis receiving and processing one or more other signals received over a respective other channel (a respective one of the STANDBY CHANNEL and the AUXILIARY CHANNELS) in the assigned frequency band, and the computing circuit722-72nof the respective receiver circuit analyzes the processed signal and determines, monitors, and tracks the quality of the respective other channel. For example, the PIC radio16, or another signal source, may transmit a respective test signal over each of the other channels (active channel monitoring), or the one or more other signals may emanate from another, unknown source (passive channel monitoring). Furthermore, the computing circuit722-72nmay store a respective history of the determined quality metrics and quality score of the respective other channel in a memory (not shown) on board the receiver circuit602-60n.

If there are enough main and auxiliary monitoring receiver circuits602-60nfor there to be at least one receiver circuit per each other channel, then each respective receiving circuitry70of the main and auxiliary receiver circuits60is tuned to receive and process signals over a single respective other channel (other than the ACTIVE CHANNEL22), and each respective computing circuitry72of the main and auxiliary receiver circuits analyzes the processed signals and monitors, determines, and tracks the quality of a single respective other channel.

But if there are not enough main and auxiliary receiver circuits60for there to be at least one receiver circuit per each other channel, then at least one of the respective main and auxiliary receiver circuits can tune its respective receiving circuitry70to receive signals over a first other channel during a first time window, to receive signals over a second other channel during a second time window, and so on, such that the respective computing circuit70analyzes the processed signals and monitors, determines, and tracks the quality of the respective other channels in a time-multiplexed manner. That is, the respective computing circuit70determines the quality of the first other channel during the first time window, determines the quality of the second other channel during the second time window, and so on. For example, if there are four main and auxiliary receiver circuits602-60n=5and eight channels (including the STANDBY CHANNEL) in the assigned sub band other than the ACTIVE CHANNEL (e.g., a total of nine channels in the sub band), then each main and auxiliary receiver circuit determines and monitors the quality of a respective two of the other channels in the above-described time-multiplexed manner. For purposes of the below-described operational example, it is assumed that there are five channels in the assigned sub band, and only one auxiliary receiver circuit60n=3. The five channels are ACTIVE CHANNEL, STANDBY CHANNEL, AUXILIARY CHANNEL1, AUXILIARY CHANNEL2, and AUXILIARY CHANNEL3.

During a first time period having a duration of, e.g., approximately 1.0 milliseconds (ms) to 1.0 seconds (s), the active receiving circuitry701receives and processes signals from the PIC16(FIG. 2) via the ACTIVE CHANNEL22, and the computing circuitry721analyzes these processed signals to determine the quality of the ACTIVE CHANNEL.

Further during the first time period, the main-channel-monitoring receiving circuitry702receives test or other signals over the STANDBY CHANNEL and processes these signals, and the computing circuitry722analyzes the processed signals and determines one or more quality metrics, and possibly a quality score, for the STANDBY CHANNEL.

Moreover during the first time period, the receiving circuitry70n=3of the auxiliary-channel-monitoring receiving circuitry60n=3receives test or other signals over AUXILIARY CHANNEL1and processes these signals, and the computing circuitry72n=3analyzes these signals and determines one or more quality metrics, and possibly a quality score, for AUXILIARY CHANNEL1.

During or after the first time period, the computing circuitry721and72n=3of the active and auxiliary receiver circuits601and60n=3provide, to the computing circuitry722of the main receiver circuit602, the respective quality metrics (and quality scores if generated) of the ACTIVE CHANNEL and AUXILIARY CHANNEL1, respectively (the computing circuitry722already “has” the quality metrics (and quality score if generated) for the STANDBY CHANNEL). The computing circuitry722stores the quality information for the ACTIVE CHANNEL, STANDBY CHANNEL, and AUXILIARY CHANNEL1in a memory circuit (not shown inFIG. 3) of the receiver circuit602. For example, the computing circuit722may store a quality history for the ACTIVE CHANNEL, STANDBY CHANNEL, and AUXILIARY CHANNEL1in the memory circuit.

After the first time period has ended, the computing circuitry722of the main receiving circuitry602tunes the receiving circuitry702to receive one or more signals over AUXILIARY CHANNEL2, and instructs the computing circuitry72n=3of the receiver circuit60n=3to tune the receiving circuitry70n=3to receive one or more signals over AUXILIARY CHANNEL3.

During a second time period having a duration of, e.g., approximately 1.0 ms to 1.0 s, which second time period can commence immediately, or a non-zero time, after the first time period, the active receiving circuitry701continues to receive and process one or more signals from the PIC16via the ACTIVE CHANNEL22(FIG. 2), and the computing circuitry721continues to determine the quality of the ACTIVE CHANNEL and to store quality information for the ACTIVE CHANNEL in memory.

Further during the second time period, the receiving circuitry702of the main receiver circuit602receives one or more test or other signals over AUXILIARY CHANNEL2and processes these signals, and the computing circuitry722analyzes these signals and determines one or more quality metrics, and possibly a quality score, for AUXILIARY CHANNEL2and stores quality information for AUXILIARY CHANNEL2in memory.

Moreover during the second time period, the receiving circuitry70n=3of the auxiliary receiver circuit60n=3receives one or more test or other signals over AUXILIARY CHANNEL3and processes these signals, and the computing circuitry72n=3analyzes these signals and determines one or more quality metrics, and possibly a quality score, for AUXILIARY CHANNEL3and stores quality information for AUXILIARY CHANNEL3in memory.

During or after the second time period, the computing circuitry721and72n=3of the active and auxiliary receiver circuits601and60n=3provide, to the computing circuitry722of the main receiving circuit602, the respective quality metrics (and quality scores if generated) of the ACTIVE CHANNEL and AUXILIARY CHANNEL3, respectively (the computing circuitry702already “has” the quality metrics (and quality score if generated) for AUXILIARY CHANNEL2). The computing circuitry722stores the quality information for the ACTIVE CHANNEL, AUXILIARY CHANNEL2, and AUXILIARY CHANNEL3in the memory circuit (not shown inFIG. 3) of the receiver circuit602.

After the second time period, the computing circuitry722of the main receiver circuit602compares the quality information for each of the ACTIVE CHANNEL22, STANDBY CHANNEL, AUXILIARY CHANNEL1, AUXILIARY CHANNEL2, and AUXILIARY CHANNEL3, and determines the following: 1) the order of these channels from the channel having the highest quality to the channel having the lowest quality, 2) which, if any, of the channels has a respective quality that is above a quality threshold stored in the memory circuit of the main receiver circuit602(not shown inFIG. 3), and which, if any, of the channels has a respective quality that is below the quality threshold.

If the computing circuitry722determines that both the ACTIVE CHANNEL22and the STANDBY CHANNEL have quality levels that are above the quality threshold, then the computing circuitry722continues to monitor, to determine, and to track the quality levels of the ACTIVE CHANNEL, STANDBY CHANNEL, AUXILIARY CHANNEL1, AUXILIARY CHANNEL2, and AUXILIARY CHANNEL3, by repeating the above-described monitoring procedure.

If, however, the computing circuitry722determines that the ACTIVE CHANNEL has a quality that is below the quality threshold, and that the STANDBY CHANNEL has a quality that is above the quality threshold, then the computing circuitry722sends, via the transmitter64, the transmit antenna66, the ACTIVE CHANNEL22(or the STANDBY CHANNEL if the quality of the ACTIVE CHANNEL is too low to carry a request signal), a request to the PIC radio16(FIG. 2) to switch the ACTIVE CHANNEL over to the STANDBY CHANNEL. The PIC radio16may switch the ACTIVE CHANNEL over to the STANDBY CHANNEL automatically, or may request, e.g., via a visual or audio notification, the pilot to perform the switch over, e.g., via a switch. After the switch over, the receiver circuit602transitions from being the main-channel-monitoring receiver circuit to the new active receiver circuit, and the receiver circuit601transitions from being the active receiver circuit to being an auxiliary receiver circuit.

If the computing circuitry722determines that the ACTIVE CHANNEL has a quality that is above the quality threshold, that the STANDBY CHANNEL has a quality that is below the quality threshold, and that at least one of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3has a quality that is above the quality threshold, then the computing circuitry722sends, via the transmitter64, the transmit antenna66, the ACTIVE CHANNEL22, and the PIC radio16(FIG. 2), a request to the assignment server20to reassign the STANDBY CHANNEL to one of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3. For example, if AUXILIARY CHANNEL3has the highest quality level of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3, then the computing circuitry722requests the assignment server20to assign AUXILIARY CHANNEL3as the new STANDBY CHANNEL.

If the assignment server20refuses the request because, for example, the requested one of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3is unavailable (e.g., is being used by another unmanned-aircraft system), then the computing circuitry722requests, via the ACTIVE CHANNEL22and the PIC radio16(FIG. 2), the assignment server to assign another of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3as the new STANDBY channel. For example, if AUXILIARY CHANNEL2has the second-highest quality level of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3after AUXILIARY CHANNEL3, then the computing circuitry722requests the assignment server to assign AUXILIARY CHANNEL2as the new STANDBY CHANNEL1.

If the assignment server20refuses the request, then the computing circuitry722repeats the above standby-channel-reassignment-request procedure for different ones of the other channels in the sub band until the assignment server approves the reassignment request. If the assignment server20approves none of the reassignment requests, then the computing circuitry722can notify, via the ACTIVE CHANNEL22, the PIC radio16(FIG. 2) that there is no current standby channel with a quality level above the quality threshold, and the PIC radio can so notify the pilot.

If, however, the assignment server20grants the request to reassign the STANDBY CHANNEL, then the receiver circuit60corresponding to the newly reassigned STANDBY CHANNEL becomes the new main receiver circuit. For example, if the assignment server20grants a request to make the AUXILIARY CHANNEL3the new STANDBY CHANNEL, then the receiver circuit60n=3becomes the new main receiver circuit, and the receiver circuit602becomes an auxiliary receiver circuit.

If the assignment server20refuses the request, then the computing circuitry722repeats the above-described standby-channel-reassignment-request procedure for different other channels in the sub band until the assignment server approves the reassignment request. If the assignment server20approves none of the reassignment requests, then the computing circuitry722can notify, via the ACTIVE CHANNEL22, the PIC radio16(FIG. 2) that there is no current standby channel with a quality level above the quality threshold, and the PIC radio can so notify the pilot.

Continuing with the operational example, if the computing circuitry722determines that both the ACTIVE CHANNEL and the STANDBY CHANNEL have qualities that are below the quality threshold, and that at least one of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3has a quality that is above the quality threshold, then the computing circuitry722sends, via the transmitter64, the transmit antenna66, the ACTIVE CHANNEL22, and the PIC radio16(FIG. 2), a request to the assignment server20to reassign the ACTIVE CHANNEL22directly to one of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3. For example, if AUXILIARY CHANNEL3has the highest quality level of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3, then the computing circuitry722requests the assignment server20to make AUXILIARY CHANNEL3the new ACTIVE CHANNEL. And if at least two of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3have qualities that are above the quality threshold, then the computing circuitry722also sends, via the transmitter64, the transmit antenna66, the ACTIVE CHANNEL22, and the PIC radio16(FIG. 2), a request to the assignment server20to reassign the STANDBY CHANNEL to another one of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3. For example, if AUXILIARY CHANNEL2has the second-highest quality level of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3, then the computing circuitry722requests the assignment server to assign AUXILIARY CHANNEL2as the new STANDBY CHANNEL.

If the assignment server20refuses the request because, for example, the requested one or two of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3is unavailable (e.g., is being used by another unmanned-aircraft system), then the computing circuitry722requests, via the ACTIVE CHANNEL22and the PIC radio16(FIG. 2), the assignment server to assign another of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3as the ACTIVE CHANNEL; and, if there are additional other auxiliary channels having qualities above the quality threshold, then the computing circuitry722requests the assignment server to assign another of these other channels as the STANDBY CHANNEL. For example, if AUXILIARY CHANNEL3has the third-highest quality level of AUXILIARY CHANNEL1-AUXILIARY CHANNEL3and this third-highest quality level is above the quality threshold, then the computing circuitry722requests the assignment server20to assign AUXILIARY CHANNEL3as the new ACTIVE CHANNEL22; and if there is at least one other channel in addition to AUXILIARY CHANNEL1-AUXILIARY CHANNEL3having a quality level above the quality threshold, then the computing circuitry722requests the assignment server to assign one of these at least one other auxiliary channels as the new STANDBY CHANNEL.

If the assignment server20refuses the request, then the computing circuitry722repeats the above active-and-standby-channel-reassignment-request procedure for different other channels until the assignment server approves the reassignment request. If the assignment server20approves none of the reassignment requests, then the computing circuitry722can notify, via the ACTIVE CHANNEL22, the PIC radio16(FIG. 2) that there is no current channel with a quality level above the quality threshold, and the PIC radio can so notify the pilot.

If the assignment server20grants the request, then the receiver circuits60corresponding to the newly reassigned ACTIVE CHANNEL and STANDBY CHANNEL become the new active receiver circuit and the new main receiver circuit, respectively. For example, if the assignment server20grants a request to make the AUXILIARY CHANNEL1the new ACTIVE CHANNEL and the AUXILIARY CHANNEL3the new STANDBY CHANNEL, then the receiver circuit602becomes the new active receiver circuit, the receiver circuit60n=3becomes the new main receiver circuit, and the receiver circuit601becomes an auxiliary receiver circuit.

Still referring toFIG. 3, alternate embodiments of the airborne radio44are contemplated. For example, alternate embodiments described above in conjunction withFIG. 2may be applicable to the airborne radio44ofFIG. 3. Furthermore, instead of each receiver circuit60having its own computing circuitry72, the airborne radio44can have computing circuitry that is common to all of the receiver circuits. Moreover, instead of including a respective receive antenna62for each receiver circuit60, the airborne radio44may include one receive antenna that is shared by all of the receiver circuits, or multiple receive antennas each shared by respective groups of the receiver circuits. In addition, instead of including the transmit antenna66, the transmitter64can be configured to transmit signals via one of the receive antennas62. For example, the airborne radio44may include only a single antenna that acts as a receive antenna for all of the receiver circuits60and that acts as a transmit antenna for the transmitter64. Furthermore, instead of requesting reassignment of the ACTIVE CHANNEL22to the STANDBY CHANNEL only if the quality of the ACTIVE CHANNEL is below the quality threshold, the main receiver circuit602may request reassignment of the ACTIVE CHANNEL to the STANDBY CHANNEL if the quality of the STANDBY CHANNEL is better than the quality of the ACTIVE CHANNEL. Furthermore, instead of requesting reassignment of the STANDBY CHANNEL to an AUXILIARY CHANNEL only if the quality of the STANDBY CHANNEL is below the quality threshold, the main receiver circuit602may request reassignment of the STANDBY CHANNEL to an AUXILIARY CHANNEL if the quality of the AUXILIARY CHANNEL is better than the quality of the STANDBY CHANNEL. Moreover, the quality threshold for one channel may be different than the quality threshold for another channel. In addition, if the airborne radio44includes only two receiver circuits601and602, then the main receiver circuit602is configured to perform all of the functions attributed to the receiver circuits602and60n=3in the above example. And, in addition to determining, monitoring, and tracking the quality of a respective channel, each of the receiver circuits60can be configured to monitor and to determine the availability of one or more respective channels other than the active and standby channels. For example, the each receiver circuit60can be configured to detect whether a respective other channel is being used for communications between a PIC radio or GRS and another unmanned aircraft.

FIG. 4is a diagram of the airborne radio44ofFIG. 2, according to another embodiment. Unlike the airborne radio44ofFIG. 3, the airborne radio44ofFIG. 4includes a single, wideband receiver circuit80, which is configured to determine the respective quality of each of the channels within the sub band that the assignment server20(FIG. 2) assigns to the airborne radio.

In addition to the receiver circuit80, the airborne radio44includes a receive antenna82, a transmitter circuit84, and a transmit antenna86.

The receive circuit80includes a preamplifier circuit88, an radio-frequency (RF) filter circuit90, an RF amplifier circuit92, an RF mixer circuit94, an intermediate-frequency (IF) filter circuit96, an IF amplifier circuit98, an IF mixer circuit100, a baseband filter circuit102, a baseband amplifier circuit104, an analog-to-digital converter (ADC)106, and computing circuitry108.

The preamplifier circuit88can be a conventional preamplifier (e.g., a low-noise amplifier) that is configured to amplify signals received by the receive antenna82over all of the channels (active, standby, and auxiliary channels) in the sub band assigned to the airborne radio44.

The RF filter circuit90is a bandpass filter that is configured to filter, from the pre-amplified signals, noise and other signals that are outside of the RF frequency range of the modulated sub band, and the RF amplifier circuit92is configured to amplify the filtered RF signals.

The RF mixer circuit94is configured to downshift, i.e., demodulate, the amplified filtered signals from RF frequencies to respective intermediate frequencies (IF).

The IF filter circuit96is configured to filter, from the demodulated signals, noise and other signals that are outside of the IF frequency range of the RF-demodulated sub band, and the IF amplifier circuit98is configured to amplify the filtered IF signals.

The IF mixer circuit100is configured to downshift, i.e., demodulate, the amplified filtered signals from IF frequencies to respective baseband frequencies.

The baseband filter circuit102is configured to filter, from the demodulated signals, noise and other signals that are outside of the baseband frequency range of the sub band, and the baseband amplifier circuit104is configured to amplify the baseband filtered signals.

The analog-to-digital converter (ADC)106is configured to convert the amplified baseband signals into a digital combined signal (i.e., a digital time-domain signal).

And the computing circuitry108is configured to recover, from the digital combined signal, the signals that the receiver circuit80respectively received over each channel (active, standby, and auxiliary channels) of the sub band. For example, the computing circuitry108can be configured to implement a Fast Fourier Transform (FFT) on the digital combined signal to recover the signals respectively received over each channel of the sub band. The computing circuitry108is also configured to recover the pilot commands carried by the signal on the active channel, and to provide the recovered pilot commands to a control and navigation system (not shown inFIG. 4) that is configured to maneuver, and to otherwise control, the unmanned aircraft42(FIG. 2) in response to the pilot commands (the computing circuitry also can be configured to provide the recovered pilot commands to another system, such as a weapons system, on board the unmanned aircraft). And the computing circuitry108is further configured to determine, monitor, and track the respective quality of each of the channels in the sub band, and to request reassignment of the ACTIVE CHANNEL and of the STANDBY CHANNEL as needed.

The receive antenna82can be any suitable receive antenna with a bandwidth wide enough to receive signals over all of the channels of the assigned sub band.

The transmitter circuit84is configured to transmit channel-reassignment requests, and possibly other signals, from the computing circuitry108to the assignment server20via the PIC radio16or a GRS18(FIG. 2) and an active channel22or24or a standby or auxiliary channel.

And the transmit antenna86can be any suitable transmit antenna.

Still referring toFIG. 4, operation of the airborne radio44is described according to an embodiment.

The receiver antenna82receives signals (actively or passively) from all of the channels of the assigned sub band on which signals are present.

The preamplifier circuit88amplifies the signals received by the antenna82, and the RF filter circuit90bandpass filters the amplified signals.

The RF mixer circuit92demodulates the filtered RF signals to respective IF signals, and the IF filter circuit94bandpass filters the IF signals.

The IF amplifier circuit96amplifies the filtered IF signals, and the IF mixer circuit98demodulates the filtered IF signals to respective baseband-frequency signals.

The baseband filter circuit100bandpass filters the baseband-frequency signals, and the baseband amplifier circuit102amplifies the filtered baseband-frequency signals.

The ADC104converts the amplified baseband-frequency signals into a combined digital signal.

The computing circuitry106subjects the combined digital signal to a FFT to recover the respective base-band frequency signal(s) received over each channel in the sub band assigned to the airborne radio44by the assignment server20(FIG. 2).

The computing circuit106recovers pilot commands from the recovered signal received over the active channel, and provides the recovered pilot commands to a navigation and control circuit (not shown inFIG. 4), and possibly other circuits (e.g., weapons circuits), on board the unmanned aircraft42(FIG. 2).

The computing circuit106also determines, monitors, and tracks the respective quality of each of the channels (active, standby, and auxiliary channels) in the assigned sub band, and requests, from the assignment server20(FIG. 2), reassignment of the active and standby channels as needed based on the qualities of the active and standby channels. For example, the computing circuitry106may request reassignment of the active channel, the standby channel, or both the active and standby channels, in a manner similar to the manner described above in conjunction withFIG. 3. And the computing circuit106can include a memory (not shown inFIG. 4) to store respective quality information, and a respective quality history, for each of the channels in the sub band.

Still referring toFIG. 4, alternate embodiments of the airborne radio44are contemplated. For example, alternate embodiments described above in conjunction withFIGS. 2 and 3may be applicable to the airborne radio44ofFIG. 4. Furthermore, in addition to determining, monitoring, and tracking the quality of a respective channel, the receiver circuit80can be configured to monitor and to determine the availability of one or more respective channels other than the active and standby channels. For example, the receiver circuit80can be configured to detect whether a respective other channel is being used for communications between a PIC radio or GRS and another unmanned aircraft.

EXAMPLE EMBODIMENTS

Example 1 includes a radio configured for disposition on an unmanned vehicle, the radio comprising: a first receiver circuit configured to receive a signal over a current active channel within a frequency sub band corresponding to the unmanned vehicle; and a second receiver circuit configured to monitor a respective availability and a respective quality of each of a current standby channel and at least one other channel within the frequency sub band while the first receiver circuit is receiving the signal, and to request an assignment of one of the at least one other channel as a new standby channel if the second receiver circuit determines that the quality of the one of the at least one other channel is better than the quality of the current standby channel.

Example 2 includes the radio of Example 1 wherein the frequency sub band is within an L frequency band.

Example 3 includes the radio of Example 1 wherein the frequency sub band is within a C frequency band.

Example 4 includes the radio of Example 1 wherein the first and second receiver circuits are a same wide-band receiver circuit.

Example 5 includes the radio of Example 1 wherein the first and second receiver circuits are a same simultaneous-multi-channel-receiving receiver circuit.

Example 6 includes the radio of Example 1 wherein the first and second receiver circuits are separate receiver circuits.

Example 7 includes the radio of Example 1 wherein the first and second receiver circuits are separate single-channel receiver circuits.

Example 8 includes the radio of Example 1 wherein one of the first and second receiver circuits is configured: to monitor a quality of the current active channel; and to request an assignment of the current standby channel as a new active channel if the one of the first and second receiver circuits determines that the quality of the current standby channel is better than the quality of the current active channel.

Example 9 includes the radio of Example 1 wherein one of the first and second receiver circuits is configured: to monitor a quality of the current active channel; and to request an assignment of one of the at least one other channel as a new active channel if the one of the first and second receiver circuits determines that the quality of the one of the at least one other channel is better than the qualities of the current active channel and of the current standby channel.

Example 10 includes the radio of Example 1 wherein the second receiver circuit is configured to request a frequency-assignment circuit to assign the one of the at least one other channel as the new standby channel if the second receiver circuit determines that the quality of the one of the at least one other channel is better than the quality of the current standby channel.

Example 11 includes the radio of Example 10, further comprising: a transmitter; and wherein the second receiver circuit is configured to cause the transmitter to request the frequency-assignment circuit to assign the one of the at least one other channel as the new standby channel if the second receiver determines that the quality of the one of the at least one other channel is better than the quality of the current standby channel.

Example 12 includes the radio of Example 10 wherein the second receiver circuit includes: first receiving circuitry configured to receive a respective other signal over each of the current standby channel and the at least one other channel; and computing circuitry configured to monitor the respective availability and the respective quality of each of the current standby channel and the at least one other channel within the frequency sub band by analyzing each respective other signal, and to request the assignment of one of the at least one other channel as a new standby channel if the computing circuitry determines that the quality of the one of the at least one other channel is better than the quality of the current standby channel.

Example 13 includes an unmanned vehicle, comprising: a radio, comprising a first receiver circuit configured to receive a signal over a current active channel within a frequency sub band corresponding to the unmanned vehicle, and a second receiver circuit configured to monitor a respective availability and a respective quality of each of a current standby channel and at least one other channel within the frequency sub band while the first receiver circuit is receiving the signal, and to request an assignment of one of the at least one other channel as a new standby channel if the second receiver circuit determines that the quality of the one of the at least one other channel is better than the quality of the current standby channel.

Example 14 includes the unmanned vehicle of Example 13 wherein the second receiver circuit is configured to request a frequency-assignment circuit to assign the one of the at least one other channel as the new standby channel if the second receiver circuit determines that the quality of the one of the at least one other channel is better than the quality of the current standby channel.

Example 15 includes the unmanned vehicle of Example 14 wherein the frequency-assignment circuit is disposed remote from the radio.

Example 16 includes the unmanned vehicle of Example 14 wherein the frequency-assignment circuit is disposed remote from the unmanned vehicle.

Example 17 includes a method, comprising: receiving a signal over an active channel within a frequency sub band corresponding to an unmanned vehicle; determining a respective availability and a respective quality of each of a current standby channel and of at least one other channel within the frequency sub band while receiving the signal; and requesting an assignment of one of the at least one other channel as a new standby channel if the quality of the current standby channel is worse than the quality of the one of the at least one other channel.

Example 18 includes the method of Example 17, further comprising: determining a quality of the current active channel; and requesting an assignment of the current standby channel as a new active channel if the determined quality of the current active channel is worse than the determined quality of the current standby channel.

Example 19 includes the method of Example 17, further comprising: determining a quality of the current active channel; and requesting an assignment of one of the at least one other channel as a new active channel if the determined quality of the current active channel is worse than the determined quality of the one of the at least one other channel.

Example 20 includes a non-transitory computer-readable medium storing instructions that, when executed by at least one computing circuit, cause the at least one computing circuit, or cause at least one other circuit under control of the at least one computing circuit: to receive a signal over an active channel within a frequency sub band corresponding to an unmanned vehicle; to determine a respective availability and a respective quality of each of a current standby channel and of at least one other channel within the frequency sub band while receiving the signal; and to request an assignment of one of the at least one other channel as a new standby channel if the quality of the current standby channel is worse than the quality of the one of the at least one other channel.

Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement, which can achieve the same purpose, may be substituted for the specific embodiments shown. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.