JMY5051 is the second generation product based on JMY505 with UART and IIC serial port. JMY5051 has various functions and supports multi ISO/IEC standard of contactless card. The RF protocol is complex. The designer combined some frequent used command of RF card and then user could operate the cards with full function by sending simple command to the module.
The impedance between RF module and antenna was tuned by impedance analyzer. And then the module has excellent performance and stability.
The module and antenna is split design. They are connecting by a 50ohm coaxial wire whose length is up to 1000cm in good situation. But the best length of the coaxial line is 60cm.