Registered User wrote:
On Mon, 13 Dec 2010 18:02:55 -0000, wrote:

Registered User wrote:
On Mon, 13 Dec 2010 00:13:10 -0000, wrote:

Registered User wrote:
On Sun, 12 Dec 2010 17:32:53 -0000, wrote:

Registered User wrote:

Efficiency is a measure so it must have one or more dimensions

Efficiency is a ratio usually expressed as a percentage and has no dimensions.

The efficiency of an antenna is the radiated power divided by the input
power.

There are two dimensions in the calculation, radiated power and input
power. Although the units of measure associated with the dimensional
data may cancel the dimensional metadata doesn't.

x power/ y power = x/y

The units cancel to form a dimensionles, unitless, ratio.

This is grade school math.

unitless yes and in the example given no metadata is provided. The
result of the calculation is just a meaningless number.

What of the equation :
x units of radiated power / y units of input power
The units cancel but the metadata doesn't. The result is a number that
describes the ratio of radiated power to input power.

2 watt / 10 watt = 0.2

No "metadata".

Yes no metadata beyond the UOM and when the UOMs cancel the result is
a bare number. Twenty percent of what?


Have you the slightest clue what the word "context" means?

"Antenna efficiency is 20%" has all the information required and if the
discussion is about antennas, "efficiency is 20%" has all the information
required.



--
Jim Pennino

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On Mon, 13 Dec 2010 19:51:07 -0000, wrote:

Have you the slightest clue what the word "context" means?

Absolutely, yes I do. In turn I will ask do you know what metadata is?
Both dimensional and non-dimensional metadata provide context.
Non-dimensional metadata doesn't always provide the complete context.
Dimensional metadata provides greater context because it conveys more
detailed and specific information.

"Antenna efficiency is 20%" has all the information required and if the
discussion is about antennas, "efficiency is 20%" has all the information
required.

When data gets shared among multiple parties it is important that a
ubiquitous language is used to describe the data and its meaning.
Antenna efficiency can be measured in different ways so the phrase
"antenna efficiency is 20%" can mean different things to different
people. All it takes is one person to ask how antenna efficiency is
calculated and it will become evident that context of "antenna
efficiency is 20%" does not provide all the information required.

When the result's context includes dimensional metadata such as "20%
antenna efficiency calculated as the ratio of power radiated to input
power" the meaning of the result and how it was calculated both are
self-evident. Everyone knows what the result means because the
dimensional metadata provides an exact definition. A mere ten words of
dimensional metadata adds succinct clarity to the result. What makes
such clarity unnecessary and/or undesirable?

On Dec 14, 5:02*am, Registered User wrote:


When data gets shared among multiple parties it is important that a
ubiquitous language is used to describe the data and its meaning.
Antenna efficiency can be measured in different ways so the phrase
"antenna efficiency is 20%" can mean different things to different
people. All it takes is one person to ask how antenna efficiency is
calculated and it will become evident that context of "antenna
efficiency is 20%" does not provide all the information required.

Sure it does. Antenna efficiency is only calculated one way,
so there is no need to add extra "metadata".
Like one said, it's redundant. In the real world, most will
calculate the efficiency of the antenna system as a whole.
Not just the radiating element/s. Even a very small dipole
vs wavelength will radiate nearly all power that is applied to it.
The trick is actually getting the power to it without it turning to
heat.
So most will calculate the whole system, otherwise it's
fairly pointless. But the efficiency of even a whole system is
still calculated the same way, and no extra "metadata" is
required to calculate. It's still the ratio between the output of the
transmitter, vs the RF actually radiated. It's been that way
since they invented dirt, so who needs metadata? I sure don't.

I'm starting to think it must be a full moon...
It's been getting pretty silly around here lately.. :/

On Tue, 14 Dec 2010 05:37:25 -0800 (PST), wrote:

On Dec 14, 5:02*am, Registered User wrote:


When data gets shared among multiple parties it is important that a
ubiquitous language is used to describe the data and its meaning.
Antenna efficiency can be measured in different ways so the phrase
"antenna efficiency is 20%" can mean different things to different
people. All it takes is one person to ask how antenna efficiency is
calculated and it will become evident that context of "antenna
efficiency is 20%" does not provide all the information required.

Sure it does. Antenna efficiency is only calculated one way,
so there is no need to add extra "metadata".

Funny thing, when working parabolic antennas antenna efficiency and
aperture efficiency are used interchangeably.

Registered User wrote:
On Tue, 14 Dec 2010 05:37:25 -0800 (PST), wrote:

On Dec 14, 5:02Â*am, Registered User wrote:


When data gets shared among multiple parties it is important that a
ubiquitous language is used to describe the data and its meaning.
Antenna efficiency can be measured in different ways so the phrase
"antenna efficiency is 20%" can mean different things to different
people. All it takes is one person to ask how antenna efficiency is
calculated and it will become evident that context of "antenna
efficiency is 20%" does not provide all the information required.

Sure it does. Antenna efficiency is only calculated one way,
so there is no need to add extra "metadata".

Funny thing, when working parabolic antennas antenna efficiency and
aperture efficiency are used interchangeably.



Regisered User and some other guy arrive at a gas station at the same time.

Other guy: "Fill'er up."

Regisered User: "Remove the gas cap, that is the covering device on the gas
tank, that is the tank, which is an enclosure, which holds the gasoline for
this car, that is a private passenger vehicle, and dispense gasoline from
your pump, that is the mechanism that dispenses gasoline, into the tank,
that is the tank intended to hold gasoline, until the fluid, in this case
gasoline, level, which is the fluid air, which is 78.1% nitorgen, 20.9%
oxygen, 0.9% argon and less than .1% other trace gases, interface, which
forms because we are on a planet with positive gravity, reaches the top,
that is the uppper most part, of the gasoline tank which holds the gasoline."

This is followed by a 20 minute dissertation on which way to turn the gas
cap to get it on and off, an explanation of how the percentages of the
various gasses than make up air are measured, the origin and history of
the gallon, and the value of the dollar relative to a loaf of bread in 1937.


--
Jim Pennino

Remove .spam.sux to reply.

The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993)
provides no definition for 'antenna efficiency' per se. A definition
is provided for 'antenna efficiency of an aperture-type antenna' in
section 2.15 of the document. The definitions are in alphabetical
order so the definition describing the ratio of power radiated to
input power appears in section 2.308 which is titled 'radiation
efficiency' (notice the dimensional metadata).

These citations from IEEE Standard Definitions Terms for Antennas
clearly suggest claims of a universal formula and definition for
antenna efficiency are incorrect. Not everyone means the same although
they use the same name. This is why it is important to define or refer
to the definitions that are used.

Registered User wrote:
The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993)
provides no definition for 'antenna efficiency' per se.

So what?

The term is in common use and can by found in many textbooks on
electromagnetics in general and antennas in particular, several books by
the ARRL as well as on many technical web pages.


--
Jim Pennino

Remove .spam.sux to reply.

On Dec 14, 12:24*pm, Registered User wrote:
On Tue, 14 Dec 2010 05:37:25 -0800 (PST), wrote:
On Dec 14, 5:02 am, Registered User wrote:

When data gets shared among multiple parties it is important that a
ubiquitous language is used to describe the data and its meaning.
Antenna efficiency can be measured in different ways so the phrase
"antenna efficiency is 20%" can mean different things to different
people. All it takes is one person to ask how antenna efficiency is
calculated and it will become evident that context of "antenna
efficiency is 20%" does not provide all the information required.

Sure it does. *Antenna efficiency is only calculated one way,
so there is no need to add extra "metadata".

Funny thing, when working parabolic antennas antenna efficiency and
aperture efficiency are used interchangeably.

I find that a funny thing, since they define two different things.
They are not the same thing, and should not be confused,
intermingled, or even paired up on the same date to go watch
Star Wars at the midnight movies.
If I were to refer to aperture efficiency, I would call it aperture
efficiency, effective aperture, or maybe even antenna effective
area, but not antenna efficiency.

Registered User wrote:
On Mon, 13 Dec 2010 19:51:07 -0000, wrote:

Have you the slightest clue what the word "context" means?

Absolutely, yes I do. In turn I will ask do you know what metadata is?

Yes, and I also know what ice cream is, both of which are irrelevant to
the discussion.

Both dimensional and non-dimensional metadata provide context.
Non-dimensional metadata doesn't always provide the complete context.
Dimensional metadata provides greater context because it conveys more
detailed and specific information.

Only an ignorant, anal retentive git would think that basic terminology has
to be defined each and every time it is used.

"Antenna efficiency is 20%" has all the information required and if the
discussion is about antennas, "efficiency is 20%" has all the information
required.

When data gets shared among multiple parties it is important that a
ubiquitous language is used to describe the data and its meaning.

The term "antenna efficiency" has a unique and unambigous definition and
can be found in any textbook on electromagnetics.

snip long winded babble


--
Jim Pennino

Remove .spam.sux to reply.

On Dec 14, 4:54*pm, wrote:
Registered User wrote:
On Mon, 13 Dec 2010 19:51:07 -0000, wrote:

Have you the slightest clue what the word "context" means?

Absolutely, yes I do. In turn I will ask do you know what metadata is?

Yes, and I also know what ice cream is, both of which are irrelevant to
the discussion.

Both dimensional and non-dimensional metadata provide context.
Non-dimensional metadata doesn't always provide the complete context.
Dimensional metadata provides greater context because it conveys more
detailed and specific information.

Only an ignorant, anal retentive git would think that basic terminology has
to be defined each and every time it is used.

"Antenna efficiency is 20%" has all the information required and if the
discussion is about antennas, "efficiency is 20%" has all the information
required.

When data gets shared among multiple parties it is important that a
ubiquitous language is used to describe the data and its meaning.

The term "antenna efficiency" has a unique and unambigous definition and
can be found in any textbook on electromagnetics.

really? i don't see either 'efficiency' or 'antenna efficiency' in
either my 2nd edition of jackson's classical electrodynamics, or
ramo,whinnery, and van duzer's fields and waves in communication
electronics... if you know where those terms might be defined in
either of those please let me know, maybe the indexes aren't complete
or something.