Power division in antenna systems for millimeter wave applications
Examples disclosed herein relate to a power division structure. The power division structure has an input port to receive a transmission signal, a plurality of output ports to transmit portions of the transmission signal to a signal structure, and a plurality of transmission paths to propagate the transmission signal from the input port to the plurality of output ports, each transmission path having an associated weight and configured with power division vias to distribute the transmission signal according to its associated weight.
1. A power division structure, comprising:
an input port to receive a transmission signal;
a plurality of output ports to transmit portions of the transmission signal to a signal structure; and
a plurality of transmission paths to propagate the transmission signal from the input port to the plurality of output ports, each transmission path having an associated weight and configured with power division vias to distribute the transmission signal according to its associated weight.
2. The power division structure of claim 1 , wherein the portions of the transmission signal have unequal power.
3. The power division structure of claim 1 , wherein a set of transmission paths in the plurality of transmission paths comprises a set of phase correction vias to maintain a phase of the transmission signal in the plurality of output ports.
4. The power division structure of claim 1 , wherein a set of transmission paths in the plurality of transmission paths comprises a set of stabilizer vias to match an input impedance.
5. The power division structure of claim 1 , wherein the associated weight in each transmission path is determined to satisfy a Chebyshev distribution.
6. The power division structure of claim 1 , wherein the plurality of transmission paths is configured in a symmetric tree structure with multiple stages, wherein in each stage a transmission path is divided into two other transmission paths.
7. The power division structure of claim 1 , comprising a layered structure formed of a top conductive layer, a dielectric layer and a reference conductive layer.
8. The power division structure of claim 7 , where in the power division structure is formed by vias lined with a conductive material to create a conductive connection from the top conductive layer through the dielectric layer and to the reference conductive layer.
9. The power division structure of claim 1 , wherein the signal structure comprises an antenna.
10. An antenna system, comprising:
a power division structure to divide a transmission signal received at an input port into unequal portions in a plurality of output ports through a plurality of transmission paths, each transmission path having an associated weight and configured with power division vias to distribute the transmission signal according to its associated weight;
an antenna having a plurality of channels, each channel connected to an output port to radiate the transmission signal into a radiation pattern; and
a metastructure connected to the antenna to direct the radiation pattern into a controlled direction.
11. The antenna system of claim 10 , wherein the antenna is an SIW antenna.
12. The antenna system of claim 11 , wherein the SIW antenna comprises a plurality of non-symmetric slots to reduce side lobes.
13. The antenna system of claim 10 , wherein a set of transmission paths in the plurality of transmission paths comprises a set of phase correction vias to maintain a phase of the transmission signal in the plurality of output ports.
14. The antenna system of claim 1 , wherein a set of transmission paths in the plurality of transmission paths comprises a set of stabilizer vias to match an input impedance.
15. The antenna system of claim 10 , wherein the associated weight in each transmission path is determined to satisfy a Chebyshev distribution.
16. A method for designing a power division structure coupled to an antenna, comprising:
identifying a desired power distribution for a plurality of output ports connected to an input port in the power division structure through a plurality of transmission paths;
determining power ratios for the plurality of transmission paths; and
building the power division structure with a plurality of power division vias to achieve the desired power distribution, a plurality of phase correction vias to achieve a desired phase and a plurality of stabilizer vias to match input impedances in the plurality of transmission paths.
17. The method of claim 16 , further comprising adjusting the input port for impedance matching.
18. The method of claim 16 , further comprising adjusting the plurality of output ports for power levels, impedance and phase.
19. The method of claim 16 , further comprising designing the antenna for impedance matching, power distribution, phase, and side-lobe performance.
20. The method of claim 16 , further comprising placing the plurality of power division vias in the power division structure according to the determined power ratios.