Methods and apparatus for rfid reader cable calibration
AssigneeSymbol Technologies, Inc.
InventorsRon Boschini, Amit Asthana, Albert Owens
Life of this patent
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Abstract
A method for calibrating an RFID reader having a transmit port and a receive port includes connecting a cable between the transmit port and the receive port, transmitting a known signal from the transmit port to the receive port through the cable, and computing a cable loss associated with the cable based on the difference between the known signal and the signal detected at the receive port. The power level of the transmit port may then be adjusted in accordance with the cable loss and a known antenna gain.
Claims17
A method for calibrating an RFID reader having a transmit port and a receive port, the transmit port having an adjustable power level, the method comprising:
- connecting a cable between the transmit port and the receive port;
- transmitting a known signal from the transmit port;
- receiving a modified signal, based on the known signal, from the receive port;
- computing a cable loss associated with the cable based on the known signal and the modified signal;
- adjusting the power level of the transmit port in accordance with the cable loss.
A RFID reader comprising:
- a transmit port configured to removeably couple to a cable;
- a receive port configured to removeably couple to the cable;
- a transmit antenna configured to removeably couple to the cable;
- a processor configured to operate the RFID reader in a normal mode and a calibration mode;
- wherein, while in the calibration mode, and the cable is coupled between the transmit port and the receive port, the processor is configured to:
- transmit a known signal from the transmit port, receive a modified signal from the receive port, and computing a cable loss associated with the cable based on the known signal and the modified signal;
A method of calibrating an RFID reader, comprising:
- connecting a cable between a first port and a second port associated with the RFID reader;
- transmitting a signal having a first power level from the first port to the second port through the cable;
- receiving a signal having a second power level at the second port during the transmitting step;
- computing a cable loss for the cable based on the difference between the first power level and the second power level;
- and
- adjusting a transmit level of the first port in accordance with the cable loss and a predetermined antenna gain to achieve an effective isotropic radiated power that is substantially equal to a target power level.
Dependencies are inferred from the claim text.