Recently, various wireless communication technologies are under development in accordance with the advancement of information communication technology. Among them, a wireless local area network (WLAN) is a technique allowing mobile terminals such as personal digital assistants (PDAs), lap top computers, portable multimedia players (PMPs), and the like, to wirelessly access the Internet at homes, in offices, or in a particular service providing area, based on a radio frequency technology.
As a technology specification that has been relatively recently legislated in order to overcome a limitation in a communication speed that has been pointed out as a weak point in the WLAN, there is the IEEE (Institute of Electrical and Electronics Engineers) 802.11n. An object of the IEEE 802.11n is to increase a speed and reliability of a wireless network and extend an operating distance of the wireless network. More specifically, the IEEE 802.11n is based on multiple inputs and multiple outputs (MIMO) technology in which multiple antennas are used at both of a transmitting end and a receiving end in order to support a high throughput (HT) having a maximum data processing speed of 540 Mbps or more, minimize a transmission error, and optimize a data speed. Further, in this specification, a coding scheme of transmitting several overlapped duplicates may be used in order to increase data reliability, and an orthogonal frequency division multiplexing (OFDM) scheme may also be used in order to increase a speed.
In the wireless communication system, codewords are generally interleaved over the entire frequency band in order to obtain a frequency diversity gain and maximize an interleaving effect. When a size of a used frequency band increases, a coding gain and a diversity gain are obtained by increasing a codeword and an interleaver to the size of the frequency band.
However, when the size of the interleaver is increased in accordance with an increase in size of the frequency band, a burden on changing an existing structure and complexity may increase.