Randomized phase and amplitude radar codes for space object tracking

1. A method of tracking objects using a radar, the method comprising:

sending a beamcode to a radar antenna to set a predetermined direction;

using samples from a random distribution of at least one of a phase or an amplitude to generate a tracking signal pulse train;

transmitting the pulse train from the radar antenna within a pulse time window;

receiving return signals from objects at the radar antenna; and

using the return signals to gather data to track the objects, wherein at least one of:

(a) wherein using a random distribution comprises: generating a first pulse train; counting a number of samples in a receive time window for the radar that are unusable due to transmitting to produce an efficiency of the first pulse train; determining a largest sidelobe in frequency space for the received signals to identify a peak sidelobe; combining the peak sidelobe and the efficiency to produce a metric; and using the metric to select a distribution to be used, or

(b) wherein using a random distribution comprises: generating a first pulse train; determining a parameter of the pulse train using the parameter to produce a metric; and using the metric to select a distribution to be used.

2. The method of tracking objects of claim 1 , further comprising having a wait time after sending the beamcode to allow for beamcode processing at the radar.

3. The method of tracking objects of claim 1 , wherein using a random distribution comprises: generating a first pulse train; counting a number of samples in a receive time window for the radar that are unusable due to transmitting to produce an efficiency of the first pulse train; determining a largest sidelobe in frequency space for the received signals to identify a peak sidelobe; combining the peak sidelobe and the efficiency to produce a metric; and using the metric to select a distribution to be used.

4. The method of claim 1 , wherein the random distribution is applied to a phase of the tracking pulse train.

5. The method of claim 1 , wherein the random distribution is applied to an amplitude of the tracking signal pulse train.

6. The method of claim 1 , wherein the random distribution is applied to a phase and an amplitude of the tracking pulse train.

7. The method of claim 1 , wherein the pulse train is adapted to occur within a duty cycle constraint.

8. The method of claim 1 , wherein the pulse train is adapted to occur within a pulse length time.

9. The method of claim 1 , wherein the random distribution is one of uniform or non-uniform.

10. The method of claim 1 , wherein using a random distribution comprises: generating a first pulse train; determining at least one parameter of the pulse train using the at least one parameter to produce a metric; and using the metric to select a distribution to be used.

11. The method of claim 10 , wherein the at least one parameter includes one of an integrated sidelobe level, a main lobe width, and a total power in the main lobe.

12. A radar system, comprising:

a radar antenna to transmit a tracking signal;

a memory to store a set of uniform, random distributions;

a controller connected to the radar antenna and the memory, the controller programmed to execute instructions to:

determine which random distribution to use;

generate a pulse train using the random distribution;

transmit the pulse train to the radar antenna as the tracking signal; and

gather measurement data about objects returning signals from the tracking signal.

13. The radar system of claim 12 , wherein the controller comprises a computing device connected to a radar controller.

14. The radar system of claim 12 , wherein the radar antenna is one element of a phased array of elements.

15. The radar system of claim 14 , wherein each element of the phased array has a controller.

16. The radar system of claim 14 , wherein the elements of the phased array of elements are divided into sub-arrays, each sub-array having a controller.