Abstract: An apparatus and a method for encrypting and decrypting data in a wireless LAN includes additional blocks for generating key sequence by a secret key and generating key sequence by ICV in order to solve disadvantages of conventional WEP apparatus and method for encrypting/decrypting data suggested by IEEE 802.11, and the key sequence by the ICV is dual-encrypted by XOR operated with the transmission data, and thereby, wiretapping and sensing from outer side can be blocked.

Abstract: An apparatus and a method for encrypting and decrypting data in a wireless LAN includes additional blocks for generating key sequence by a secret key and generating key sequence by ICV in order to solve disadvantages of conventional WEP apparatus and method for encrypting/decrypting data suggested by IEEE 802.11, and the key sequence by the ICV is dual-encrypted by XOR operated with the transmission data, and thereby, wiretapping and sensing from outer side can be blocked.

Abstract: A carrier wave restoring apparatus which is capable of restoring a carrier wave quickly and accurately by selectively controlling an operation of a matching filter. The carrier wave restoring apparatus comprises a filtering unit for filtering a broadcast signal and outputting a match filtering signal; a multiplier for receiving the matching filtering signal and generating an ‘I’ (Inphase) signal and a ‘Q’ (Quadrature) signal; an error detector for accumulating a sign bit of a DC component of the ‘I’ signal, comparing it with a predetermined threshold, and outputting a control signal to the filtering unit; and a gain controlling unit for receiving the ‘I’ signal and the ‘Q’ signal from the multiplier and outputting a gain control signal to control a carrier wave restoration velocity according to the control signal of the error detector.