Wireless Sensor Network (WSN) is a network that consists of low rate devices, to sense, collect and transmit collected data using wireless communication. IEEE 802.11 (Wi-Fi) is another communication standard that is rapidly being implemented in smart devices like laptops and mobile devices. IEEE 802.11 has faster data rate, wider coverage area and bigger data per packet compared to IEEE 802.15.4. This makes IEEE 802.11 suitable for big data transmission, such as multimedia data. However, there is a limitation in IEEE 802.11 which only able to send data in the same Service Set Identifier (SSID). The original IEEE 802.11 is infrastructure based which does not allow multi-hopping transmission between distributed nodes. Implementing IEEE 802.11 standard to WSN node requires new software or Application Programming Interface (API) to handle communication between the node and transmitter. In this thesis, an API is developed based on Serial Interface Protocol provided by transmitter firmware. The API includes all the configuration parameters that need to be configured when operating the transmitter for normal operation such as sending and receiving packet data. An Autoconfiguration API is introduced to allow multi-hop transmission. Wi-Fi WSN node can use Auto-configuration API to disconnect from current network and connect to other nearby network and forward its data. This allows the data to be collected from the nearby network and indirectly extends the coverage area. The end-to-end delay for sending a picture in one hop transmission using Wi-Fi WSN is 20% faster compared to IEEE 802.15.4 WSN. The Wi-Fi WSN is also able to transfer data from a network to other network using Auto-configuration API using two methods which are One Joiner and All Creator (OJAC) and Some Joiner and Some Creator (SJSC) in two and three hops transmission. Result show OJAC performs 22% better in two hops transmission while in three hops transmission, SJSC performs 18% better.
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