FIELD

This present inventive concept relates generally antennas and, more particularly, to ultra-wideband antennas and related elements.

BACKGROUND

In the early 2000s, ultra-wideband (UWB) was cited as a promising technology as “wireless universal serial bus (USB)”. However, the market turned in a different direction. Nonetheless, the groundwork from the Federal Communications Commission (FCC) was laid so that devices could operate legally in the United States and abroad. Until recently, UWB devices operating in the 3.1 to 10 GHz range tended to be composed of discrete components having a relatively high price point. Recently, however, UWB integrated circuit (IC) chips have come into the marketplace allowing for lower cost UWB transceivers to be built and sold. With the lower price point, these devices may reach a broader audience with greater manufacturing quantities.

Inherent in UWB technology is the ability to create narrow pulse widths. These pulse widths can be used to establish an arrival time of a radio frequency (RF) signal with very high granularity. A precise timestamp can be determined for receiving a signal and transmitting a signal. When timestamps are compared for a message that is sent from one device to the next, a distance between devices can be calculated based on the difference in time and the speed of the signal through the air.

For determining location using Time-difference-of-Arrival, the devices typically need to be synchronized to a master clock. Conventional devices use cable based timing systems or a form of a wireless synching solution to address the synchronization issue.

SUMMARY

Some embodiments of the present inventive concept provide methods for synchronizing multiple transceivers to a single master clock, the method including broadcasting a message from a master device, the broadcasted message including a device identification number identifying the master device to at least one known device within range of the master device; receiving the message at the at least one other known device and recording a time of arrival (Tarrival-kd) at the at least one other known device; repeatedly broadcasting and receiving messages and recording associated times of arrival at the at least one other known device; and applying a fit curve to the recorded arrival times to estimate a time of an event.

In further embodiments, the fit curve may be applied to two recorded arrival times.

In still further embodiments, the fit curve may be applied to more than two arrival times.

In some embodiments, the broadcast message may include a time of transmission (Tdepart-md).

In further embodiments, both the master device and at least one known device may be radio frequency devices configured to send data at a precise time and record a timestamp of received data within a certain degree of precision.

In still further embodiments, the method may further include rebroadcasting the message from the at least one known device, the message including the transmitted time stamp in the master device time units; and receiving, at a device that is out of RF range of the master device, such that the device that is out of range is synchronized to the master device even when out of RF range using the at least one known device as an intermediate master broadcaster.

In some embodiments, the method may further include rebroadcasting the message including the transmitted time stamp in master device time units from device that is out of RF range; receiving the rebroadcasted message at a second device that is out of RF range of the master device; and synchronizing the second device that is out of RF range by using the device that is out of RF range as an intermediate master broadcaster.

In further embodiments, the method may further include receiving a broadcast time synchronization signal at the at least one known device from a plurality of master devices; and applying a weighting algorithm to the plurality of signals to determine an arrival time of the message.

In still further embodiments, the method may further include applying a weighting algorithm comprises averaging.

Some embodiments of the present inventive concept provide a known device in a network including a plurality of known devices and a master device, the known device includes a receiver configured to receive a broadcast message from a master device that is broadcast to the plurality of known devices within range of the master device, the broadcast message including a device identification number identifying the master device; and a processor configured to: record a time of arrival (Tarrival-kd) of the broadcast message at the known device, wherein the receiver receives a plurality of broadcast messages and the processor records a time of arrival for each of the plurality of broadcast messages; and apply a fit curve to the recorded arrival times to estimate a time of an event.

Further embodiments of the present inventive concept provide a system including a plurality of devices synchronized to a single master clock, the system including a plurality of known devices including a processor; and a master device configured to broadcast a message, the broadcasted message including a device identification number identifying the master device to at least one of the plurality of known devices within range of the master device; wherein the at least one of the plurality of known devices receives the broadcasted message and records a time of arrival (Tarrival-kd); wherein the master device is configured to repeatedly broadcast messages; and wherein the at least one of the plurality of known devices is configured to receive the messages and record associated times of arrival and apply a fit curve to the recorded arrival times to estimate a time of an event.

