Methods and systems for scheduling the transmission of localization signals and operating self-localizing apparatus
Localization systems and methods for transmitting timestampable localization signals from anchors according to one or more transmission schedules. The transmission schedules may be generated and updated to achieve desired positioning performance. For example, one or more anchors may transmit localization signals at a different rate than other anchors, the anchor transmission order can be changed, and the signals can partially overlap. In addition, different transmission parameters may be used to transmit two localization signals at the same time without interference. A self-localizing apparatus is able to receive the localization signals and determine its position. The self-localizing apparatus may have a configurable receiver that can select to receive one of multiple available localization signals. The self-localizing apparatuses may have a pair of receivers able to receive two localization signals at the same time. A bridge anchor may be provided to enable a self-localizing apparatus to seamlessly transition between two localization systems.
1. A localization system, comprising:
a plurality of positioning anchors configured to wirelessly transmit localization signals capable of being used by self-localizing apparatus within a region to determine position information, wherein:
a first positioning anchor of the plurality of the positioning anchors is configured to wirelessly transmit first localization signals;
a second positioning anchor of the plurality of the positioning anchors is configured to wirelessly transmit second localization signals;
a third positioning anchor of the plurality of the positioning anchors is configured to wirelessly transmit third localization signals; and
each of the plurality of positioning anchors is communicatively coupled to at least one scheduling unit, wherein the at least one scheduling unit is configured to:
schedule the transmission of the localization signals to control positioning performance within the region by:
scheduling the first positioning anchor to transmit the first localization signals at a first transmission rate;
scheduling the second positioning anchor to transmit the second localization signals at a second transmission rate; and
scheduling the third positioning anchor to transmit the third localization signals at a third transmission rate, wherein the first transmission rate is greater than the second transmission rate to provide greater positioning performance within a portion of the region.
2. The localization system of claim 1 , wherein the at least one scheduling unit is further configured to adjust the transmission rate of the localization signals to change the positioning performance within the region during operation.
3. The localization system of claim 2 , wherein the at least one scheduling unit is configured to adjust the transmission rate of the localization signals based on a known location of the self-localizing apparatus.
4. The localization system of claim 3 , wherein the at least one scheduling unit is configured to receive the known location of the self-localizing apparatus.
5. The localization system of claim 2 , wherein the at least one scheduling unit is configured to adjust the transmission rate of the localization signals based on a known motion of the self-localizing apparatus.
6. The localization system of claim 5 , wherein the motion is a flight pattern.
7. The localization system of claim 1 , wherein the localization signals comprise ultra-wideband (UWB) localization signals, each comprising a preamble code and a payload.
8. The localization system of claim 7 , wherein the payload of at least some of the UWB localization signals comprises commands and wherein the at least one scheduling unit is configured to schedule the transmission of the UWB localization signals to optimize the propagation of the commands to at least one of a self-localizing apparatus and the plurality of the anchors.
9. The localization system of claim 7 , wherein each of the plurality of positioning anchors comprises a clock, wherein the payload of at least some of the UWB localization signals comprises synchronization data, wherein each of the plurality of positioning anchors is configured to receive the synchronization data from UWB localization signals received from at least one other positioning anchor, and wherein the at least one scheduling unit is configured to schedule the transmission of the UWB localization signals to optimize the synchronization of the clocks.
10. The localization system of claim 9 , wherein each of the plurality of positioning anchors comprises a synchronization unit, wherein each synchronization unit is configured to compute a correction for at least one of a clock offset and a clock rate for its respective clock based on the received synchronization data.
11. The localization system of claim 1 , wherein the at least one scheduling unit is configured to schedule the transmission of the localization signals to increase at least one of precision, accuracy, or update rate in one or more portions of the region.
12. The localization system of claim 1 , wherein the at least one scheduling unit is configured to schedule the transmission of the localization signals based on time slots in a schedule, wherein the first positioning anchor is assigned more time slots in the schedule than the second positioning anchor.
13. The localization system of claim 1 , wherein the at least one scheduling unit comprises a first scheduling unit, a second scheduling unit, and a third scheduling unit, wherein the first scheduling unit is physically coupled to the first positioning anchor and is configured to schedule the transmission of the first localization signals, wherein the second scheduling unit is physically coupled to the second positioning anchor and is configured to schedule the transmission of the second localization signals, and wherein the third scheduling unit is physically coupled to the third positioning anchor and is configured to schedule the transmission of the third localization signals.
14. The localization system of claim 1 , wherein the region comprises a three-dimensional region.
15. A method for transmitting localization signals in a localization system comprising a plurality of positioning anchors, the method comprising:
wirelessly transmitting, using a first positioning anchor of the plurality of positioning anchors, first localization signals during two or more time slots of a transmission schedule;
wirelessly transmitting, using a second positioning anchor of the plurality of positioning anchors, second localization signals during one or more time slots of the transmission schedule; and
wirelessly transmitting, using a third positioning anchor of the plurality of positioning anchors, third localization signals during one or more time slots of the transmission schedule, wherein:
the first localization signals, the second localization signals, and the third localization signals are capable of being used by self-localizing apparatus within a region to determine position information; and
the first positioning anchor is assigned more time slots in the transmission schedule than the second positioning anchor to provide greater positioning performance within a portion of the region.
16. The method of claim 15 , further comprising:
adjusting, using one or more scheduling units, the number of time slots the first positioning anchor, the second positioning anchor, and the third positioning anchor are assigned in the transmission schedule during operation.
17. The method of claim 16 wherein the number of time slots are adjusted based on a known location of the self-localizing apparatus.
18. The method of claim 17 , further comprising wirelessly receiving the known location of the self-localizing apparatus.
19. The method of claim 16 , wherein the time slots of the transmission schedule are assigned based on one or more of a known location of the self-localizing apparatus, optimization of propagation of commands included as part of at least some of the first, second, and third localization signals, optimization of synchronization of clocks associated with the first, second, and third positioning anchors, and at least one of improved precision, accuracy, or update rate in one or more portions of the region.
20. The method of claim 15 , further comprising:
generating, using a first clock, first timing signals used to determine when the first positioning anchor wirelessly transmits the first localization signals;
generating, using a second clock, second timing signals used to determine when the second positioning anchor wirelessly transmits the second localization signals; and
generating, using a third clock, a third timing signal used to determine when the third positioning anchor wirelessly transmits the third localization signals, wherein the first, second, and third clocks are synchronized.