Transmission level point
Encyclopedia
In a telecommunications system
, a transmission level point (TLP) is a test point or interface, i.e. a physical point in an electronic circuit
where a test signal may be inserted or measured, and for which the nominal power
of the test signal is specified.
A zero dBm transmission level point (or synonym zero transmission level point) is a transmission level point where the nominal test signal power is 0dBm.
In practice, the abbreviation TLP is usually used, and it is modified by the nominal level for the point in question. For example, where the nominal level is 0 dBm
, the expression 0 dBm TLP, or simply, 0TLP, is used. Where the nominal level is −16 dBm, the expression −16 dBm TLP, or −16TLP, is used.
The nominal transmission level at a specified TLP is a function of system design and is an expression of the design gain
or loss.
Voice-channel
transmission levels, i.e. TLPs, are usually specified for a frequency
of approximately 1,000 Hz.
The TLP at a point at which an end instrument
, e.g. a telephone
set, is connected is usually specified as 0 dBm
.
System
System is a set of interacting or interdependent components forming an integrated whole....
, a transmission level point (TLP) is a test point or interface, i.e. a physical point in an electronic circuit
Electronic circuit
An electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors and diodes, connected by conductive wires or traces through which electric current can flow...
where a test signal may be inserted or measured, and for which the nominal power
Power (physics)
In physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
of the test signal is specified.
A zero dBm transmission level point (or synonym zero transmission level point) is a transmission level point where the nominal test signal power is 0dBm.
In practice, the abbreviation TLP is usually used, and it is modified by the nominal level for the point in question. For example, where the nominal level is 0 dBm
DBm
dBm is an abbreviation for the power ratio in decibels of the measured power referenced to one milliwatt . It is used in radio, microwave and fiber optic networks as a convenient measure of absolute power because of its capability to express both very large and very small values in a short form...
, the expression 0 dBm TLP, or simply, 0TLP, is used. Where the nominal level is −16 dBm, the expression −16 dBm TLP, or −16TLP, is used.
The nominal transmission level at a specified TLP is a function of system design and is an expression of the design gain
Gain
In electronics, gain is a measure of the ability of a circuit to increase the power or amplitude of a signal from the input to the output. It is usually defined as the mean ratio of the signal output of a system to the signal input of the same system. It may also be defined on a logarithmic scale,...
or loss.
Voice-channel
Channel (communications)
In telecommunications and computer networking, a communication channel, or channel, refers either to a physical transmission medium such as a wire, or to a logical connection over a multiplexed medium such as a radio channel...
transmission levels, i.e. TLPs, are usually specified for a frequency
Frequency
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...
of approximately 1,000 Hz.
The TLP at a point at which an end instrument
End instrument
In telecommunications an end instrument is an equipment connected to the wires at the end of a telecommunications link. In most cases, this is a telephone. End instruments that relate to DTE include Printers, Computers, barcode readers, Automated Teller Machines and the console ports of routers....
, e.g. a telephone
Telephone
The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...
set, is connected is usually specified as 0 dBm
DBm
dBm is an abbreviation for the power ratio in decibels of the measured power referenced to one milliwatt . It is used in radio, microwave and fiber optic networks as a convenient measure of absolute power because of its capability to express both very large and very small values in a short form...
.