Programmable scheduling machine

What is a controlled telephone exchange

Principle of controlled telephone exchange

1. Controller: The controller is the core of the controlled telephone exchange, responsible for the control and management of the entire exchange. It operates based on programs to establish, connect, and terminate phone calls according to user instructions and signals.
2. Switching matrix: The switching matrix is a key component of the controlled telephone exchange, used to connect and switch phone lines. It routing calls from the calling party to the called party based on the controller's instructions to establish connections.
3. Signaling system: The signaling system is used to transmit call control information and user data. It employs digital signal processing technology to convert user call requests and other control information into digital signals, which are then transmitted over digital channels.
4. User terminal: The user terminal is the device through which users communicate with the controlled telephone exchange, such as telephones or fax machines. Users can dial, answer calls, and engage in voice communication or data transmission through these devices.

Applications of controlled telephone exchange

1. Telephone communication: Controlled telephone exchanges are essential for enabling phone calls. They facilitate phone line access, call initiation, connection, and termination, providing high-quality voice communication services.
2. Data transmission: In addition to voice communication, controlled telephone exchanges can also enable data transmission. Users can send data to other users through devices like fax machines.
3. Value-added services: Controlled telephone exchanges can also provide value-added services such as voice mail, call forwarding, and conference calls. These features enhance users' communication efficiency and convenience.

Operational steps of controlled telephone exchange

1. Dialing: Users first need to dial the target phone number. They can input the number using the dialing keyboard on their telephones.
2. Call establishment: After dialing, the controlled telephone exchange processes the call setup based on the dialed signal. The exchange routes the call request to the corresponding terminal based on the recipient's number.
3. Call: Once the call is successfully established, users can engage in conversation. They can communicate verbally through the telephone's receiver and microphone.
4. End of call: After the conversation ends, users can hang up the phone, ending the call. The controlled telephone exchange releases the occupied line resources and returns to a standby state, ready for the next call.

Summary