IR-UWB Chipless RFID Reader Based on Frequency Translation Technique for Decoding Frequency-Coded Tags

The impulse radio ultra-wideband (IR-UWB) reader is the most promising technique to interrogate a frequency-coded chipless radio frequency identification (RFID) tag. However, challenges of receiving an ultra-wideband (UWB) pulse, such as complexity, high-noise bandwidth, low reading speed, and high cost, are yet to be addressed in IR-UWB readers. A combined solution based on an IR-UWB transmitter and a frequency translation (FT) method in the receiver is presented in this article. The tag is interrogated by a broadband pulse (3.1-10.6 GHz). In the receiver, instead of processing the entire wideband backscattered pulse in one run, the new architecture transposes the spectrum of the backscattered pulse to a 150-MHz intermediate frequency (IF) band. Hence, the noise bandwidth, cost, and complexity of the receiver are reduced significantly. Since the reading range plays a decisive role in reducing the complexity and cost, a detailed study of the design parameters of the reader, affecting the detection range, is performed. Then, a low-cost and straightforward reader is implemented, based on the outcomes of the parameters' study. It is shown that the reading range of the reader is competitive with that of the state-of-the-art readers and vector network analyzer (VNA), while the complexity, reading time, and cost are dropped.