1. Field of Invention
The invention relates to a packet type arbitrator and its arbitrating method. More particularly, the invention pertains to an arbitrator that determines packet types in a wireless local area network (WLAN) and the method thereof.
2. Related Art
In network systems, such as a wireless local area network (WLAN) system, data transmissions are done in packets. Different types of packets have different packet types. This is determined by the agreed protocol.
Generally speaking, a network system follows a single network protocol. One single packet type is enough to complete the communication tasks. However, based upon some particular reasons, such as concerns about compatibility, packet of many different types can exist in the same network system. Therefore, data to be transmitted from the sending end may exist in the form of any packet type. The receiving end without any assistant information has to automatically determine the received packet type and thus to decode the data in a corresponding way.
For example, two packet types simultaneously exist in the IEEE802.11 g WLAN system: the complementary code keying (CCK) packet and the orthogonal frequency division multiplexing (OFDM) packet. In such network systems, the receiver does not know the packet type of each packet to be received. It has to decide which type the packet has according to the information embedded in the preamble of the packet. When making decisions about the packet type, erroneous decisions sometimes occur due to noises. Thus, how to prevent incorrect decisions is an important issue to be solved in the field.