Key Features
The main objective of our project is the production of an RFID Tag Reader that can read multiple tags. In addition, we want it to have the following characteristics:
List of Material
Below, you can find a list of all the materials and equipment needed to carry out this project.
| Quantity | Description | |
|---|---|---|
| AS3992 UHF RFID Reader | 1 | RFID reader with an associated microcontroller, providing protocol support for ISO18000-6C |
| RF SOLUTIONS ANT-PCB4242-FL | 1 | UHF antenna with 50Ω impedance matching and MMCX connector |
| Barrel connector to female wire connectors | 1 | |
| The Kennedy Group - SmartTherm RFID Tags | 6 | UHF RFID EPC Gen 2 transponder tags |
| Raspberry Pi 5 | 1 | Single-board computer with wireless LAN and Bluetooth connectivity |
| Raspberry Pi 5 power supply | 1 | 15.3W maximum output power, USB-C connector |
| Female-Female jumper connectors | 5 |
System Description
This system's goal is to allow easier inventory checking in closed-spaces using RFID tag detection. Using the Raspberry Pi 5 as a host for the system, two data connections are established, one between the host and the AS3992 RFID Reader (via UART, with power been supplied via USB), and the second via BLE (Bluetooth Low Emission) with a smartphone, or any other device able to connect via BLE.
After a succesful BLE connection between the host and the phone, the user selects (through the WebApp) a list of items already logged into the server, and associate to an ID and to the serial number (EPC Gen 2) of the a certain tag. That list is sent to the host, who checks the input sent by the RFID reader. Then, a list of all detected tags is sent to the host, who will compare it with the list sent by the phone. The host will mark which items are detected and which are not, send that information to the phone, relaying that information to the WebApp, informing the user of any changes.
It is required that the system is connected at all times to a power supply, able to supply 5V, at peak 1A (5W).
Electrical Specifications
The electrical specifications of our solution were obtained through calculations and datasheets of the components integrated into our system.
| Supply Voltage (Vs) | 5V (maximum 6V) |
|---|---|
| Working power (peak) | 8.4W |
| Working power (standby) | 4.2W |
| Reading Distance | 0.70m (max.) |
| Tag Protocol | ISO18000-6C (EPC Gen. 2) |
| Tag Area | 90mm x 1mm |
| Working Frequency | 920MHz |
| RF power | 20dBm (0.5W) max |
| RFID reader receive sensitivity | -86dBm (2.51 x 10-12W ) |
| Minimum power supply requirements | 5V @ 3A (15W) |
| Antenna Gain | 5dBi @ 920MHz |
| Antenna Area | 49.5mm x 49.5mm |
Range Tests
The tests were performed with 40 consecutive readings and the success rates were recorded, as can be seen in the figure below
To access the datasheets of the components, please contact us through the contacts tab.