1. Development of a Bluetooth based web camera module

2. 1. Objective System development of Bluetooth-based applications 2. Task Hardware design of a Bluetooth camera module using the TDK Systems serial module and reference design from Emblaze 3. Basic education required System development, TCP/IP and Bluetooth protocols. 4. The report To give the reader a good understanding of the technique that has been Used to design the camera

3. In this seminar 1. Bluetooth 1) About Bluetooth 2) Protocol architecture 3) The Piconet, The Scatternet 4) States 5) Security 2. TDK Bluetooth Intelligent Serial Module 1) Facts 2) RF performance 3. ER4520 Multimedia and Application Coprocessor Video Codec Features 4. Difficulty of realization : Low picture quality

4. About Bluetooth 1. Cable replacement 2. The range of each radio is approximately 10m, but can be extended to 100m with an amplifier 3. Ad hoc networking Not required a line-of-sight connection 4. Using the 2.4 GHz band ( Radio frequency )

5. Protocol architecture

6. Core protocol 1.Application program interface(API), Service discovery protocol(SDP) 2. Logical Link Control and Adaptation Protocol (1) maintaining individual links to other devices (2) data formatting from the application type to Bluetooth transmittable formats (3) multiplexing of the various links into one stream 3. Link Manager Protocol (1) establishing and terminating links to other devices (2) Authentication of new links, in order to preserve security 4. Baseband : The data is sequenced into packets while error correction and encryption data is added as headers on the payload(user's data) 5. Bluetooth Radio : The actual radio transmitter and antenna

7. Cable replacement protocol RFCOMM (radio frequency communications) 1.RFCOMM presents a virtual serial port 2.RFCOMM enables the replacement of serial port cables with the minimum of modification of existing device 3.RFCOMM provides for binary data transport and emulate RS-232 signals over the baseband layer

8. Piconet, Scatternet 1.Piconet 1) Bluetooth network with one master and one or more slaves There can be up to seven active slaves in a piconet (3 bits Active Member address) and 256 parked devices(8 bits Parked member address) 2) Each piconet is identified by a different frequency hopping sequence 2. Scatternet When two piconets are close to each other, they have overlapping coverage area. Each of the piconets operates in its own frequency-hopping channel while any devices in multiple piconets participate at the appropriate time, via time division multiplexing

9. States The sub states are interim states which are used to add new slaves to a piconet

10. Security 1. None : All Bluetooth devices are allowed to connect. 2. Authorization : the local device operator must authorize a remote device connection, usually by physically clicking an on screen button. 3. Authentication : remote device must provide a password that matches that of the local device 4. Encryption : connections with remote devices can be encrypted for additional security. Some Bluetooth devices do not support encruption.

11. TDK Bluetooth Intelligent Serial Module (Facts)

12. RF performance

13. ER4520 Multimedia and Application Coprocessor The ER4520 is a full duplex audio/video codec based on the ARM920T core as a high performance, fully programmable processor Video Codec Features QCIF1 resolution (176x144) up to 144 Kbps Video streaming : 30 fps decode only Video mail : 15 fps encode only Video phone (full duplex) : 12 fps encode and decode Advanced error resilience and error concealment algorithms Advanced pre and post processing to improve picture quality PIP (picture in picture) support JPEG encode/decode up to VGA resolution

14. The low picture quality The serial communication is too slow to transfer streaming video.

15. Alternative Solution Using Parallel cameras and USB cameras 1.Parallel cameras The parallel camera is in conflict with serial module that uses the serial interface. There was no easy way to get around this problem. skip 2. USB cameras (1) Bluetooth module can not handle USB interface a) The adapter can only make a serial port from a USB port. b) a USB connection must be between a host and a device. (2)Different Bluetooth modules were used that had USB inputs. Not as in this case a device to device

16. Calculations Using UART UART data rate : 115200 bps QCIF : 176 × 144 pixels and 16 fps compression rate : 8 × 176 × 144 × 16 / 115200 = 28.16 Using USB (using maximum Bluetooth data rate) Bluetooth data rate : 720000 bps QCIF : 458 × 344 pixels and 16 fps CIF : 352 × 288 pixels and 30 fps compression ratio : 8 × 352 × 288 × 30 / 720000 = 33.80 MPEG-4 codec estimates this compression ratio

17. Results The purpose of the work is to design a Bluetooth web camera. Maximum resolution : QCIF (176 x 144) and 16 fps Maximum bit rate with current software : 70 kbit/s The maximum speed of Bluetooth module : 200 kbit/s The camera has the bottleneck for the picture resolution. USB cameras : better picture resolution

18. Q & A