Fundamental Principles of Telecom Network Engineering
Classified in Technology
Written on in 
English with a size of 5.3 KB
LAN Design Constraints
Answer: The main constraints when designing Local Area Networks (LANs) include economy, geographical extension, the number of people, and call habits.
Subscriber Circuit Length Limits
Answer: Parameters that limit the length of the subscriber circuit are attenuation limits, the signaling driver, and resistance.
Benchmark Frequencies: Europe & USA
Answer: The high benchmark frequencies are 1000Hz (USA) and 800Hz (Europe).
Subscriber Circuit Design Criteria
Answer: The basic criteria that apply to the design of subscriber circuits are signaling, attenuation, and resistance.
Electrical Resistance Formula
Answer: The formula for calculating the electrical resistance of a conductor is: R = ρL/A (where R is resistance, ρ is resistivity, L is length, and A is cross-sectional area).
Resistivities of Common Elements
Answer: The approximate resistivities (in Ohm-meters, Ω·m) of the following elements are:
- Copper: 1.72 x 10⁻⁸ Ω·m
- Aluminum: 2.63 x 10⁻⁸ Ω·m
- Gold: 2.44 x 10⁻⁸ Ω·m
- Silver: 1.47 x 10⁻⁸ Ω·m
Subscriber Satisfaction Evaluation Method
Answer: The method used to evaluate the satisfaction of the subscriber is the Equivalent Reference method.
Unit for Telecom Level Loss
Answer: The unit that measures telecommunications level loss is Decibels (dB).
International Telecom Regulator
Answer: The international body regulating telecommunications is the International Telecommunication Union (ITU).
ERR and ERT Acronym Meanings
Answer:
- ERR: Equivalent Reference Rating
- ERT: Equivalent Reference Transmission
Maximum ERT for International Connections
Answer: The recommended maximum ERT for an international connection is 33 dB.
Defining International Connections in Local Areas
Answer: In a local area, an international connection is considered one that originates and ends within the local area but crosses international boundaries.
Fade Limit Source
Answer: The fade limit is taken from the transmission of the national plan and is 6 dB.
Resistance Limits Determination
Answer: The switch determines the limits of resistance, which is 1,250 ohms.
Understanding Pupinization
Answer: Pupinization is a technique that tends to lower losses in transmission subscriber circuits and other types of voice communication.
Line Conditioning Methods for Extended Limits
Answer: Other methods of line conditioning circuits used to extend beyond the allowed limits include extending the power amplifier line.
Loaded Cable Characteristics (Code 19H88)
Answer: For a loaded cable with code 19H88, the characteristics include:
- Gauge (19)
- Coil separation (H)
- Inductance (88 millihenries, mH)
Factors Determining Central Area Size
Answer: The size served by a central area is a function of the density and distribution of subscribers.
Standard Central Office Capacity
Answer: The capacity of a standard central office is 10,000 lines.
Large Central Office Line Capacity
Answer: A large central office could have up to 140,000 lines.
Optimal Central Office Location Method
Answer: A simple and direct method to calculate the optimal theoretical location of the central office is the Center of Gravity method.
Service Area Division for Location Planning
Answer: To apply the previous method, a service area is typically divided into blocks, such as 100x100 or 500x500 units.
Data Integration for Planning Tables
Answer: Each planning table integrates data such as:
- Existing subscribers
- Subscribers on the waiting list
- Subscriber forecasts for the following 15 to 29 years
Center of Gravity Calculation
Answer: The center of gravity is calculated by finding the intersection of two lines: a horizontal line with approximately the same number of subscribers above and below it, and a vertical line with the same number of subscribers to its left and right.
S1 and CS Column Representation
Answer: In planning tables, S1 represents the sum along a single line, and CS represents the cumulative sum.
Actual Central Office Location Determination
Answer: Once the theoretical location is established, the actual central office location is determined by considering practical factors such as land availability, cost, existing infrastructure, and accessibility.