User's Manual

Table Of Contents

RFI341 Radio Frequency Interrogator

ISO/IEC 15693-2 Air Interface and Initialisation

This part of ISO/IEC 15693 describes the electrical characteristics of the

contactless interface between the transponder and the interrogator. The

interface includes power and bi-directional communications.

Initial Dialog for ISO15693 Transponder

• Activating of the transponder (interrogator RF power on)

• Transponder waiting for a command from the interrogator (ITF)

• Receiving the command from the interrogator

• Transmitting the response to the interrogator

Power Transfer

The power transfer from the interrogator antenna to the transponder is

accomplished by radio frequency via coupling antennas. The RF operating

field that supplies power to the transponder from the interrogator is

modulated for communication.

Frequency

The transponder frequency is 13.56 MHz ± 7 kHz

Communications Signal Interface

For some parameters, special modes are available to comply with different

international radio regulations and application requirements.

Modulation

Communications between interrogator and transponders takes place using

the ASK modulation principle. If the modulation index is set to 100 %, the

noise sensitivity is less. A modulation index of, e.g., 20 % will increase the

read/write performance but also increase the noise sensitivity.

Data Rate and Data Encoding

The transponder support two data coding modes

(1 out of 4 at 26.48 kbit/sec and 1 out of 256 at 1.65 kbit/sec).