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The path loss for the first ten kilometers may be 150 -- 190 dB ( Note: These values are very approximate and are given here only as an illustration of the range in which the numbers used to express the path loss values can eventually be, these are not definitive or binding figures -- the path loss may be very different for the same distance along two different paths and it can be different even along the same path if measured at different times.
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Nevertheless, these financially troubled leagues, by beginning the practice of selling players to the more affluent National and American leagues, embarked on a path that eventually led to the loss of their independent status.
Similarly, the energy loss per unit path length, the ' stopping power ', depends on the type and energy of the charged particle and upon the material.
In telecommunication, free-space path loss ( FSPL ) is the loss in signal strength of an electromagnetic wave that would result from a line-of-sight path through free space ( usually air ), with no obstacles nearby to cause reflection or diffraction.
Free-space path loss is proportional to the square of the distance between the transmitter and receiver, and also proportional to the square of the frequency of the radio signal.
Path loss ( or path attenuation ) is the reduction in power density ( attenuation ) of an electromagnetic wave as it propagates through space.
In the study of wireless communications, path loss can be represented by the path loss exponent, whose value is normally in the range of 2 to 4 ( where 2 is for propagation in free space, 4 is for relatively lossy environments and for the case of full specular reflection from the earth surface — the so-called flat-earth model ).
In some environments, such as buildings, stadiums and other indoor environments, the path loss exponent can reach values in the range of 4 to 6.
On the other hand, a tunnel may act as a waveguide, resulting in a path loss exponent less than 2.
In its simplest form, the path loss can be calculated using the formula
where is the path loss in decibels, is the path loss exponent, is the distance between the transmitter and the receiver, usually measured in meters, and is a constant which accounts for system losses.
Radio and antenna engineers use the following simplified formula ( also known as the Friis transmission equation ) for the path loss between two isotropic antennas in free space:
where is the path loss in decibels, is the wavelength and is the transmitter-receiver distance in the same units as the wavelength.
Calculation of the path loss is usually called prediction.
For practical cases the path loss is calculated using a variety of approximations.
For FM radio and TV broadcasting the path loss is most commonly predicted using the ITU model as described in P. 1546 ( former P. 370 ) recommendation.
These methods are expected to produce more accurate and reliable predictions of the path loss than the empirical methods ; however, they are significantly more expensive in computational effort and depend on the detailed and accurate description of all objects in the propagation space, such as buildings, roofs, windows, doors, and walls.
path and for
From above one could only occasionally catch a glimpse of life on the floor of this green sea: a neighbor's gingham skirt flashing into sight for an instant on the path beneath her grape-arbor, or the movement of hands above a clothesline and the flutter of garments hung there, half-way down the block.
Abstract art was still the right path for him ; ;
The pressure for our entry to the Common Market is mounting and we will proceed towards this amalgamated trade union by way of a purely `` economic thoroughfare '', or garden path, with the political ramifications kept neatly in the background.
The president has little influence in day-by-day curricular changes, but if he looks ahead two, three, or five years to anticipate issues and throw out challenging ideas, he can open the way for innovation, and he can also have a great deal to say as to what path it will take.
But even before that, Picasso had glimpsed and entered, for a moment, a certain revolutionary path in which no one had preceded him.
It was foggy that evening, but the path to my house was so well grooved that I could feel my way, accustomed as I was to the dense mists that rise from the sun-warmed palisades of the river and sometimes last for days.
The ones who do not follow the path after all will get hints for a better reincarnation.
The pursuit of wisdom, he assured his readers of the Boethius, was the surest path to power: " Study Wisdom, then, and, when you have learned it, condemn it not, for I tell you that by its means you may without fail attain to power, yea, even though not desiring it ".
He who gives in charity and fears Allah And in all sincerity testifies to the Truth ; We shall indeed make smooth for him the path of Bliss
Steiner's stated prerequisites to beginning on a spiritual path include a willingness to take up serious cognitive studies, a respect for factual evidence, and a responsible attitude.
The historic path to autonomy was a concern for secure sources of heat, power, water and food.
A nearly parallel path toward autonomy has been to start with a concern for environmental impacts, which cause disadvantages.
Thus for an ion which traverses a 1 m flight path, across a time of 2000 ns, given an initial accelerating voltage of 5000 V and noting that one amu is 1 × 10 < sup >− 27 </ sup > kg, the mass-to-charge ratio ( more correctly the mass-to-ionisation value ratio ) becomes Z amu / charge.
Users outline the wanted path in Bézier curves, and the application creates the needed frames for the object to move along the path.
The enemy directly in their path ... realised to their horror that Athenians, far from providing the easy pickings for their bowmen, as they had first imagined, were not going to be halted ...
He viewed Christ as the cause and reason for the reconciliation of man with God after the fall of Adam, and he saw in Christ the path to Christian salvation.
In 2003 USAID considered Croatia to be on a " glide path for graduation " along with Bulgaria.
The existing stream usually acts as the water source and its banks provide a path for the new body.
For surveys, the most common approach is to follow a historical path by associating stances with the philosophers who are most strongly associated with them, for example Descartes, Locke, Kant, etc.
Its message is purely a spiritual one, an allegory of the spiritual path, which is equally relevant in all ages and for all people.
This is because coalitions would necessarily include different parties with differing beliefs and who, therefore, may not always agree on the correct path for governmental policy.
The particles of the solid stationary phase or the support coated with a liquid stationary phase may fill the whole inside volume of the tube ( packed column ) or be concentrated on or along the inside tube wall leaving an open, unrestricted path for the mobile phase in the middle part of the tube ( open tubular column ).
The village gave its name to Cheddar cheese and has been a centre for strawberry growing, with the crop being transported on the Cheddar Valley line, which closed in the late 1960s but is now a cycle path.
A great deal of strategy and teamwork goes into choosing the ideal path and placement of a stone for each situation, and the skills of the curlers determine how close to the desired result the stone will achieve.
path and first
If the decision goes wrong, it may be -- as Mr. Stevenson fears -- `` the first step on the slippery path downhill '' to a U.N. without operational responsibilities and without effective meaning.
It is one of the five Yamas ( restraints ) which make up the code of conduct, the first of the eight limbs of which this path consists.
He described how fire gave rise to the other elements as the: " upward-downward path ", (), a " hidden harmony " or series of transformations he called the " turnings of fire ", (), first into sea, and half that sea into earth, and half that earth into rarefied air.
The folder and file names are separated by slashes in this example ; the topmost or root folder has no name, and so the path begins with a slash ( if the root folder had a name, it would precede this first slash ).
The first demonstrates that extracting " which path " information after a particle passes through the slits can seem to retroactively alter its previous behavior at the slits.
The first recitation of the Guru Granth Sahib called the Japji Sahib says the following: " The path of the faithful shall never be blocked.
In this first book Bopp entered at once the path on which he would focus the philological researches of his whole subsequent life.
Two such morphisms are composed by first following the first path, then the second ; the homotopy equivalence guarantees that this composition is associative.
Among the gnostics, gnosis was first and foremost a matter of self-knowledge, which was considered the path leading to the goal of enlightenment as the hidden knowledge of the various pre-Judeo-Christian pagan Mystery-Religions.
In 1979 the ( non relativistic ) hydrogen atom was solved for the first time within Feynman's path integral formulation
The first economy to follow this path in the modern world was the United Kingdom.
He completed his first film at 13 ; in college he studied economics with the goal of continuing his father's business, but an interest in class issues distracted him from that path.
The South Melbourne ground was in the path of Victoria ’ s first steam railway line from Melbourne to Sandridge ( now Port Melbourne ).
* 1993 – The Intel Corporation ships the first Pentium chips ( 80586 ), featuring a 60 MHz clock speed, 100 + MIPS, and a 64 bit data path.
The paths an LSR knows can be defined using explicit hop-by-hop configuration, or are dynamically routed by the constrained shortest path first ( CSPF ) algorithm, or are configured as a loose route that avoids a particular IP address or that is partly explicit and partly dynamic.
In 1906, Roald Amundsen first successfully completed a path from Greenland to Alaska in the sloop Gjøa.
In 1972, the first formal summit meeting between Pyongyang and Seoul was held, but cautious talks did not lead much of anywhere and relations between the two Koreas continued down the path of hostility.
Another construction simulates NTMs with 3-tape DTMs, of which the first tape always holds the original input string, the second is used to simulate a particular computation of the NTM, and the third encodes a path in the NTM's computation tree.
A similar path was pursued by the Bee Gees, formed in Brisbane, but whose first album Bee Gees ' 1st ( 1967 ), recorded in London, gave them three major hit singles and contained folk, rock and psychedelic elements, heavily influenced by the Beatles.
In the first, more philosophically oriented phase, Steiner attempted to find a synthesis between science and mysticism ; his philosophical work of these years, which he termed spiritual science, sought to provide a connection between the cognitive path of Western philosophy and the inner and spiritual needs of the human being.
In areas where vehicles were confined to a single path ( a mountain road, swamps, snow, urban areas ), RPG teams trapped convoys by destroying the first and last vehicles in line, preventing movement of the other vehicles.
Spain continued on the path of economic growth when the ruling party changed in 2004, maintaining robust GDP growth during the first term of prime minister José Luis Rodríguez Zapatero, even though some fundamental problems in the Spanish economy were now becoming clearly evident.
Rofé had been searching for a spiritual path and became the first non-Indonesian to be opened.
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