A Wireless Multimedia Player Based on 802.11b and StongARM Processor

• Main Authors: Chif-Pin Tang, 湯志斌
• Other Authors: Jhing-Fa Wang
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/8hnp6t

碩士 === 國立成功大學 === 電機工程學系碩博士班 === 90 === In the data transmission area, visual communication is not only a direct way but also an effective form of expression. With the continuing growth of wireless network, an embedded wireless multimedia player must be an important electronic device in the future market. For instance, we can use a mobile phone with image expression function. There are several multimedia devices with the benefit of multifunction, for instance, PDA, Webpad and Tablet, etc., but the cost is higher than the device with single function. For example, if we just want music; we can choose an MP3 player instead of PDA. In this case, we proposed a specialized multimedia player with better image quality and high competition of price. The basic idea of our “Inseparable Image” is to make a wireless multimedia player based on a TFT LCD and a StrongARM processor. In the aspect of wireless communication, the 802.11b is used as our Wireless LAN transmission protocol. The multimedia streams are transmitted from a server over the Ethernet to the Access Point, and every player can receive them under wireless environment. By means of this portability, users can receive the real-time data stream in everywhere they are, and it is why we call it “Inseparable Image”. By using digital transmission, several benefits such as high quality, easy to store and compatible with other device, etc., are also obtained. According to the ARM Linux kernel, the modifications of drivers, O.S., audio/video output library, drivers and application programs are proposed. As the StrongARM processor doesn’t provide the capability of floating-point computation, we also proposed a fix-point solution for it. Due to modularized designing style, the bandwidth and image quality supported by the proposed system can be easily upgraded by better wireless protocol or technology in the future. We have done the experiment of multi channel playing mode, 4 players can work simultaneously with one access point and keep good image quality. In comparison with the iPAQ PDA, our system also has better performance. Besides, we also have the capability of real-time encoding and decoding. In summary, we designed a low cost, high performance software and hardware structure focused on multimedia playing. Our system also has high flexibility to achieve various applications such as information appliance, secure system, digital TV, advertisement board, bulletin board, etc.