Points to Make Low-Power UHF Handheld RFID Reader-1.test005.dyyseo.cn

Points to Make Low-Power UHF Handheld RFID Reader

2017/06/06

UHF RFID readers can be divided into fixed RFID readers and handheld readers. Handheld readers achieved a large number of applications for its portable, and easy to use in shift data collection.

It is difficult to design handheld UHF RFID reader, because it covers embedded computer application, microwave and antenna, radio frequency electronic circuit, wireless communications and signal processing, low-power control and many other technical fields.

Based on the ARM9 chip S3C2440 of Samsung Corporation (SAMSUN), the UHF reader ASIC AS3990 of Austria Microsystems Corporation (AG) and a nine-channel programmable DC-DC power manager with battery charger SMB122 of Summit Microelectronics Corporation, a low power handheld UHF RFID reader is designed, and its lowpower control program is analyzed and designed in detail.

When the system is in working state, power is consumed mainly by RF transmitter circuit. MATLAB simulation and experimental measurements indicated that UHF RFID read range is determined by several combined factors, such as reader's transmitting power, VCO's noise strength, circulator's isolation, antenna's gain and so on. When the transmitting power reaching a certain value, continue increasing the transmitting power does not lead to a further increase of read range, the read range is decided by backward link constraint at this time.