Millimeter-Wave Uniform Amplitude SIW Series Power Divider for 2D Leaky-Wave Antenna Arrays

This paper proposes a millimeter-wave uniform amplitude substrate integrated waveguide (SIW) series power divider for 2D leaky-wave antenna arrays, which is built by connecting 10 elaborately designed unit cells in series. The unit cell consists of an SIW to slot and microstrip line coupling structure, which can be further extended to a low-cost phase shifter by introducing varactors or other active components. Theoretical analysis is made firstly to specify the necessary conditions for uniform amplitude power division. Then, a short via is added to the unit cell to meet the admittance condition. A full wave simulation is conducted to extract the normalized admittance and transmission characteristics of the unit cell, which provides useful references for the design of geometric parameters. After the design of unit cells, a 1-to-10 SIW series power divider is implemented by connecting unit cells with aimed transmission characteristics. At last, comparisons are made between the uniform amplitude power divider and the non-uniform amplitude power divider to demonstrate the feasibility of the design method. The proposed uniform amplitude SIW series power divider for 2D leaky-wave antennas works between 24 GHz and 29 GHz, which is competitive for millimeter-wave communication and wireless power transfer systems.