COMPACT SIZE HIGH GAIN CIRCULARLY POLARIZED ANTENNA FOR RFID READER AND ATTACH CLAMP THERE OF

A compact size high gain circularly polarized antenna for an RFID(Radio Frequency IDentification) reader and a clamp therefor are provided to prevent a surface wave from being generated by forming first and second radiators to be apart from a reflective board. The compact size high gain circularly polarized antenna for an RFID reader includes a reflective board(100), a radiating board(200), and a feeding line portion(300). A power divider(110) for supplying a signal power is formed on the reflective board. The radiating board is apart from the reflective board in a normal direction and includes first and second radiators and a feeding portion. Two vertical folded dipoles are symmetrically formed on the first radiator. The second radiator is formed to be normal to the first radiator. The feeding portion supplies signals to the first and second radiators, respectively. The feeding line portion supplies a signal to the feeding portion, such that signals with a phase difference of 90 degrees are supplied to the first and second radiators, respectively.