Element level polarization synthesis network for electronically scanned arrays
Systems and methods of controlling signal polarization for an antenna system are provided herein. The antenna system includes an ultra wide band or greater array of dual linear polarization elements. The antenna system also includes polarization synthesis networks. Each of the polarization synthesis networks is coupled to the first differential interface of the first element of a respective dual linear polarization element of the dual linear polarization elements and the second differential interface of the second element of the respective the dual linear polarization element of the dual orthogonal linear polarization elements. Each of the polarization synthesis networks has a flat response for phase shift and amplitude over the ultra wide bandwidth.
1. An antenna system, comprising:
an ultra wide band or greater array of dual linear polarization elements, each of the dual linear polarization elements being disposed in a respective one-half wavelength by one-half wavelength unit size, the dual linear polarization elements comprising a first element have a first differential interface and a second element having a second differential interface; and
a plurality polarization synthesis networks, wherein each of the polarization synthesis networks is coupled to the first differential interface of the first element of a respective dual linear polarization element of the dual linear polarization elements and the second differential interface of the second element of the respective the dual linear polarization element of the dual orthogonal linear polarization elements, wherein each of the polarization synthesis networks has a flat response for phase shift and amplitude over the ultra wide band width.
2. The antenna system of claim 1 , wherein each of the polarization synthesis networks comprises a first variable gain amplifier coupled in series with the first differential interface, a second variable gain amplifier coupled in series with the second differential interface, a first phase shifter coupled in series with the first variable gain amplifier, a second phase shifter coupled in series with the second variable gain amplifier, and a combiner coupled in series with a first output of the first phase shifter and a second output of the second phase shifter, and wherein the respective one-half wavelength by one-half wavelength unit size is at the highest frequency for the ultra wide band or greater array.
3. The antenna system of claim 1 , wherein first phase shifter comprises a quadrature generator in series with a third variable gain amplifier, a fourth variable gain amplifier and a combiner in series with the third variable gain amplifier and the fourth variable gain amplifier.
4. The antenna system of claim 1 , wherein an instantaneous bandwidth is 4 to 1 for the array.
5. The antenna system of claim 1 , wherein each of the polarization synthesis networks comprises a first mixer coupled in series with the first differential interface, a second mixer coupled in series with the second differential interface, a first variable gain amplifier coupled in series with the first mixer, a second variable gain amplifier coupled in series with the second mixer, a first phase shifter coupled to the first mixer, a second phase shifter coupled to the second mixer, and a combiner coupled in series with a first output of the first mixer and a second output of the second mixer.
6. The antenna system of claim 5 , further comprising
a first band pass filter coupled in series with the first mixer; and
a second band pass filter coupled in series with the second mixer.
7. The antenna array of claim 1 , wherein the dual linear polarization elements are associated with a first level of hierarchically arranged array architecture, and the polarization synthesis networks provide beam steering and polarization synthesis for the first level, and a second level of the hierarchically arranged array architecture achieves beam steering using time delay units.
8. The antenna array of claim 1 , wherein the polarization synthesis networks provide both beam steering and polarization synthesis for the array.
9. The antenna array of claim 1 , wherein the polarization synthesis networks are configured to provide a dual linear orthogonal response for the first element and the second element when the first element and the second element are non-orthogonal dipole pairs.
10. The antenna array of claim 1 , wherein the first element and the second element are a non-orthogonal dipole pair, wherein the polarization synthesis network is configured to provide an arbitrary polarization response for the non-orthogonal dipole pair.
11. An antenna system, comprising:
an array of dual linear polarization elements, each of the dual orthogonal linear polarization elements comprising a first element having a first differential interface and a second element having a second differential interface; and
a plurality polarization synthesis networks configured to provide both beam steering and polarization synthesis for the array, wherein each of the polarization synthesis networks has a flat response of phase shift and amplitude over the ultra wide bandwidth, and wherein each of the polarization synthesis networks is coupled to the first differential interface of the first element of a respective the dual linear polarization element of the dual linear polarization elements and the second differential interface of the second element of the respective the dual linear polarization element of the dual linear polarization elements, and wherein each of the polarization synthesis networks comprises:
a first variable gain amplifier comprising a low noise amplifier for providing differential amplitude rations for right hand elliptical polarization and left hand elliptical polarization coupled in series with the first differential interface;
a second variable gain amplifier comprising a low noise amplifier for providing differential amplitude rations for right hand elliptical polarization and left hand elliptical polarization coupled in series with the second differential interface;
a first analog modulo phase shifter coupled in series with either the first variable gain amplifier, or each of a third variable gain amplifier, a fourth variable gain amplifier, and a combiner coupled in series with each of the third variable gain amplifier and the fourth variable gain amplifier;
a second analog modulo phase shifter coupled in series with the second variable gain amplifier;
and a combiner coupled in series with a first output of the first analog modulo phase shifter and a second output of the second analog modulo phase shifter.
12. An antenna system, comprising:
an array of dual linear polarization elements, each of the dual orthogonal linear polarization elements comprising a first element having a first differential interface and a second element having a second differential interface;
a plurality polarization synthesis networks configured to provide both beam steering and polarization synthesis for the array at an intermediate phase shifting frequency, wherein each of the polarization synthesis networks is coupled to the first differential interface of the first element of a respective the dual linear polarization element of the dual linear polarization elements and the second differential interface of the second element of the respective the dual linear polarization element of the dual linear polarization elements, wherein each of the polarization synthesis networks comprises a first mixer coupled in series with the first differential interface, a second mixer coupled in series with the second differential interface, a first variable gain amplifier coupled in series with the first mixer, a second variable gain amplifier coupled in series with the second mixer, a first phase shifter coupled to the first mixer, a second phase shifter coupled to the second mixer, and a combiner coupled in series with a first output of the first mixer and a second output of the second mixer;
a first band pass filter coupled in series with the first mixer; and
a second band pass filter coupled in series with the second mixer.
13. A method of providing phase coincidence for a pair of antenna elements comprising first linear polarized element and a second linear polarized element in an array, wherein the phase center of the first element and the second element are not physically aligned, the method comprising:
providing a first phase control signal to a first phase shifter for the first element in a polarization network;
providing a first amplitude control signal for the first element to a first variable gain amplifier in the polarization synthesis network;
providing a second phase control signal to a second phase shifter for the second element in the polarization network; and
providing a second amplitude control signal for the second element to a second variable gain amplifier in the polarization synthesis network, wherein the first phase control signal, the second phase control signal, the first amplitude control signal, and the second amplitude control signal are provided to provide polarization and beam steering for the array, wherein the first phase control signal or the second phase control signal are provided to align electrically the phase center of the first element and the second element.
14. The method of claim 13 , wherein the first amplitude control signal, and the second amplitude control signal are provided to reduce axial ratio corruption and wherein the polarization synthesis network is provided at an element level associated with the array.