Antenna assembly with multiple layers with similar coefficients of thermal expansion
In accordance with various embodiments of the present disclosure, a radome assembly for use with an antenna assembly includes a radome body portion having a first side and a second side. The radome assembly further includes an outer layer formed from a first material, configured to be coupled to the first side of the radome body portion, and configured to be exposed to an environment of the radome.
1 . An antenna assembly comprising:
at least one antenna layer formed using a printed circuit board (PCB); and
at least one spacer layer having a body portion and a plurality of cell walls extending out of the body portion, the at least one spacer layer formed from a polymer having a polymer coefficient of thermal expansion (CTE) that is significantly different than an antenna layer CTE of the at least one antenna layer, the at least one spacer layer further including a first plurality of fibers distributed within the polymer of the body portion and a second plurality of fibers distributed within the polymer of the plurality of cell walls to cause the at least one spacer layer to have a combined CTE that is less than or equal to three times that of the at least one antenna layer, wherein the first plurality of fibers extend in at least a first direction and the second plurality of fibers extend in a second direction, the second direction being different than the first direction.
2 . The antenna assembly of claim 1 , wherein the at least one antenna layer includes a first antenna layer and a second antenna layer, and wherein the at least one spacer layer includes an antenna spacer configured to space the first and second antenna layers from one another.
3 . The antenna assembly of claim 2 , wherein the antenna spacer includes a plurality of cell walls formed into a honeycomb or other patterned arrangement, the honeycomb or other patterned arrangement defining volumes filled with air.
4 . The antenna assembly of claim 3 , wherein the plurality of cell walls of the antenna spacer define a cell having a vertical pathway and form a continuous wall around the vertical pathway.
5 . The antenna assembly of claim 1 , wherein the plurality of cell walls define a plurality of cells that each include a vertical pathway.
6 . The antenna assembly of claim 5 , wherein at least two cell walls defining a cell of the plurality of cells are spaced apart from each other.
7 . The antenna assembly of claim 6 , wherein the second plurality of fibers in the at least one spacer layer extend along a plane defined by a respective cell wall of the plurality of cell walls.
8 . The antenna assembly of claim 1 , wherein the body portion is formed monolithic with the plurality of cell walls.
9 . The antenna assembly of claim 1 , wherein the combined CTE of the at least one spacer layer is less than or equal to twice that of the at least one antenna layer.
10 . The antenna assembly of claim 1 , wherein the combined CTE of the at least one spacer layer is less than or equal to that of the at least one antenna layer.
11 . The antenna assembly of claim 1 , wherein the first and second plurality of fibers include glass fibers.
12 . The antenna assembly of claim 1 , wherein the polymer includes at least one of polypropylene (pp), polycarbonates, Polybutylene terephthalate (PBT), polyphenylene ether (PPE), Poly(p-phenylene oxide) (PPO), polystyrene (PS), polyethylene terephthalate (PET), polyvinyl chlorine (PVC), and liquid crystal polymer.
13 . The antenna assembly of claim 1 , wherein the at least one spacer layer has a thermal conductivity value of less than 0.35 watts per meter-kelvin (W/(m-K).
14 . The antenna assembly of claim 1 , wherein the combined CTE of the at least one spacer layer is less than or equal to 45 parts per million per degree Celsius (ppm/° C.).
15 . The antenna assembly of claim 1 , wherein the combined CTE of the at least one spacer layer is less than or equal to 34 parts per million per degree Celsius (ppm/° C.).
16 . The antenna assembly of claim 1 , wherein the combined CTE of the at least one spacer layer is less than or equal to 17 parts per million per degree Celsius (ppm/° C.).
17 . The antenna assembly of claim 1 , wherein adhesive is omitted adjacent the at least one spacer layer.
18 . The antenna assembly of claim 1 , wherein adhesive is omitted between the at least one spacer layer and any other layer of the antenna assembly.
19 . An antenna assembly comprising:
at least one antenna layer formed using a printed circuit board (PCB) and having an antenna layer coefficient of thermal expansion (CTE);
a PCB assembly having a PCB CTE; and
at least one spacer layer having a body portion and a plurality of cell walls extending out of the body portion, the at least one spacer layer formed from a polymer having a polymer coefficient of thermal expansion (CTE) that is significantly different than the antenna layer CTE and the PCB CTE, the at least one spacer layer further including a first plurality of fibers distributed within the polymer of the body portion and a second plurality of fibers distributed within the polymer of the plurality of cell walls to cause the at least one spacer layer to have a combined CTE that is less than or equal to three times the antenna layer CTE and less than or equal to three times the PCB CTE, wherein the first plurality of fibers extend in at least a first direction and the second plurality of fibers extend in a second direction, the second direction being different than the first direction.
20 . The antenna assembly of claim 19 , wherein the at least one spacer includes an antenna spacer and a radome spacer portion that each have the combined CTE that is less than or equal to three times the antenna layer CTE and less than or equal to three times the PCB CTE.
21 . The antenna assembly of claim 20 , wherein the at least one antenna layer, the PCB assembly, the antenna spacer, and the radome spacer portion are coupled together without use of an adhesive.
22 . A spacer for an antenna assembly, comprising:
a body portion formed from a polymer and having a first plurality of fibers distributed within the polymer; and
a plurality of cell walls extending out of the body portion, wherein the plurality of cell walls is formed from the polymer and have a second plurality of fibers distributed within the polymer forming the cell walls, wherein the first plurality of fibers extend in at least a first direction and the second plurality of fibers extend in a second direction, the second direction being different than the first direction.