Seavey Engineering has developed highly innovative means for feeding waveguide array antennas in a true-time-delay fashion.
The design technique uses special folded waveguide junctions which are carefully impedance matched for broad bandwidth performance. Typical junction bandwidth is about 25%. The array’s bandwidth limit is then determined by the array element bandwidth.
A further Seavey Engineering innovation halves the requisite number of array elements through the use of "boxhorn"-style radiators. These are simple, short rectangular horns which have a precise combination of TE10 and TE30 field modes. This combination can be shown to closely simulate the radiation properties of a pair of rudimentary waveguide slots with significantly less mutual coupling between elements.
The advantage of this approach is that the power combiner feed system has half the number of outputs. This greatly simplifies the array design and construction and reduces the overall thickness and cost.
In the complete embodiment of this design, the entire array including all radiating elements and their feeding network can be CNC machined from solid metal using only a thin cover plate over the waveguide junctions. Therefore, highly precise computer-aided design of these arrays can be easily carried out even at millimeter wavelengths with ordinary machine shop equipment and with no need to dip braze complex waveguide hybrids and waveguide onto the array in layers.
This technology can be extended into production by casting the entire microwave assembly in one piece.
Due to the binary nature of the waveguide junctions, these arrays are constructed in modules. Array size is determined by how the modules are joined.
This catalog page describes modules with approximately square dimensions.
More than seventy separate designs have been carried out to date at frequencies from 3.6 to 40 GHz. Multiple-panel arrays assembled using several single panels connected with external waveguide power dividers are also available, see Page 73.
 Model 9126(17)-800 17.7 - 19.7 GHz 37 dBi |
 Model 9648-835 - Front View 37 - 40 GHz 37 dBi |
 Model 9648-835 - Rear View 37 - 40 GHz 37 dBi |
  Model 9666-835 Front & Rear Views 24.5 - 26.5 GHz 35 dBi |
 Model 9709-835 21.2 - 23.6 GHz 35 dBi |
 Typical Array Power Divider Detail (9777-800) |