design a high-efficiency rectifier circuit using various couplers for microwave power transmission

This paper presents an optimized microwave rectifier circuit that integrates various couplers to enhance rf-to-dc conversion efficiency. a comprehensive theoretical analysis and performance evaluation of different microwave couplers are conducted to determine their impact on power distribution and impedance matching. the study demonstrates that incorporating couplers into the rectifier circuit effectively reduces reflected power over a broad input power range. among the evaluated configurations, the rectifier incorporating a branch-line coupler (blc) exhibits superior rf-to-dc efficiency over a wide range of operating frequencies, input power levels, and output loads, ensuring broad impedance matching. to validate the proposed design, a rectifier circuit based on the blc is implemented and fabricated at 2.45 ghz. the prototype consists of two identical sub-rectifying networks connected to the two output ports of the coupler, with the isolated port grounded. experimental results indicate that the rectifier consistently achieves efficiency levels exceeding 50% for input power levels ranging from 0 to 12.5 dbm. additionally, the design maintains high efficiency across a frequency range of 2.16 to 2.96 ghz. these findings underscore the potential of blc-based rectifiers for high-efficiency microwave power transmission systems, offering enhanced energy harvesting capabilities and improved system performance.