A broadband efficient rectenna array for wireless energy harvesting

This paper presents an efficient rectenna array to harvest ambient wireless energy over a broad bandwidth. An RF field measurement campaign has been undertaken at various locations in the city centre area of Liverpool. The results have been used to identify the available frequency bands and the corresponding power density levels. Thus a new wideband rectenna array has been designed and optimized to match with the ambient signals. Both the simulated and test results show that the rectenna array is highly efficient with 20 - 70% conversion efficiency over the broad band and signal levels of interest. The measured output power in reality is higher than the other published results in such as [5]-[8] with a similar input power level.