23-06-2012, 03:15 PM
Bluetooth Home Telephone System
[attachment=25271]
INTRODUCTON
The purpose of the Bluetooth Home Telephone System is to amplify the standard home telephone system with the basic communication features of one or several mobile cellular phones. The goal is to produce a system that will allow a user to respond to an incoming call directed to a Bluetooth enabled mobile phone from any of the land-line based home telephones within the home. This user-oriented product will allow a person to monitor their mobile phone from different locations within the home. This is to be achieved without the intervention of the call forwarding service provided by the mobile phone service provider.
DESIGN ARCHITECTURE
The overall design for the Bluetooth Home Telephone System is primarily composed of two parts. The first would be the Gateway Interface which is primarily composed of software. The second would be the Gateway Adapter which is hardware-based. Also important are the communication components has involvement in both parts.
Hardware Design
The chosen design presents a global perspective on the outline of the overall report. From the larger points to the smallest part, it will re-examine the stated specifications for what they were described and how they actually look like.
The Gateway Adapter
The Gateway Adapter will link with the cell phone once a connection is paired. When a call is received the flow of audio will be redirected towards the home phone and back to the cell phone. This flow from the Gateway Adapter will be heard on the speaker part and once responding on the microphone part, it will be transmitted back to the Gateway Adapter and again back to the cell phone.
The WT32
The WT32 Bluegiga chip is a Bluetooth module which has been chosen for its numerous set of Bluetooth profiles, most importantly the one required for this project, HFP (Hand Free Profile), which is an extension of the HSP (Headset Profile) in which the requirements define the minimum set of functions such that a mobile phone can be used in combination with a hand free device. For this project it will be the home telephone.
ATmega 16
The function of the microcontroller is to perform logical operation as defined by the software and proceed to generating an electrical output. Furthermore, the ATmega16 microcontroller has some important built-in functions: A UART module that shall be interfaced for wireless communications. And will be used for input flow and for output flow. Furthermore; control on the analog outputs will also be used to control the different part of the circuit.
Bridge Transformer
The use of this transformer is to convert a 4-wire into a 2-wire, while keeping the circuit in balance with the actual phone line. So impedance matching and sidetone have to be taken into consideration to transmit and receive a sufficient current to the required parts without the echo and the noise being part of it.
Ring Generator
Since a response is needed to know if a call is being received and to pick up the actual phone. A ring is used which is the intended standard used in telephony today. For example, your phone ring and you go to pick up the phone. As you pick up the phone the flow of information from the Bluegiga is transmitted to the speaker and vice versa as you speak to the microphone. A sensor on/off hook as part of the circuit is used for the purpose of the 2 states on hook or off hook of the home phone.
[attachment=25271]
INTRODUCTON
The purpose of the Bluetooth Home Telephone System is to amplify the standard home telephone system with the basic communication features of one or several mobile cellular phones. The goal is to produce a system that will allow a user to respond to an incoming call directed to a Bluetooth enabled mobile phone from any of the land-line based home telephones within the home. This user-oriented product will allow a person to monitor their mobile phone from different locations within the home. This is to be achieved without the intervention of the call forwarding service provided by the mobile phone service provider.
DESIGN ARCHITECTURE
The overall design for the Bluetooth Home Telephone System is primarily composed of two parts. The first would be the Gateway Interface which is primarily composed of software. The second would be the Gateway Adapter which is hardware-based. Also important are the communication components has involvement in both parts.
Hardware Design
The chosen design presents a global perspective on the outline of the overall report. From the larger points to the smallest part, it will re-examine the stated specifications for what they were described and how they actually look like.
The Gateway Adapter
The Gateway Adapter will link with the cell phone once a connection is paired. When a call is received the flow of audio will be redirected towards the home phone and back to the cell phone. This flow from the Gateway Adapter will be heard on the speaker part and once responding on the microphone part, it will be transmitted back to the Gateway Adapter and again back to the cell phone.
The WT32
The WT32 Bluegiga chip is a Bluetooth module which has been chosen for its numerous set of Bluetooth profiles, most importantly the one required for this project, HFP (Hand Free Profile), which is an extension of the HSP (Headset Profile) in which the requirements define the minimum set of functions such that a mobile phone can be used in combination with a hand free device. For this project it will be the home telephone.
ATmega 16
The function of the microcontroller is to perform logical operation as defined by the software and proceed to generating an electrical output. Furthermore, the ATmega16 microcontroller has some important built-in functions: A UART module that shall be interfaced for wireless communications. And will be used for input flow and for output flow. Furthermore; control on the analog outputs will also be used to control the different part of the circuit.
Bridge Transformer
The use of this transformer is to convert a 4-wire into a 2-wire, while keeping the circuit in balance with the actual phone line. So impedance matching and sidetone have to be taken into consideration to transmit and receive a sufficient current to the required parts without the echo and the noise being part of it.
Ring Generator
Since a response is needed to know if a call is being received and to pick up the actual phone. A ring is used which is the intended standard used in telephony today. For example, your phone ring and you go to pick up the phone. As you pick up the phone the flow of information from the Bluegiga is transmitted to the speaker and vice versa as you speak to the microphone. A sensor on/off hook as part of the circuit is used for the purpose of the 2 states on hook or off hook of the home phone.