How to solve the Free Space Path Loss formula (Logarithms)
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I don't have a strong mathematical understanding of logarithms so I would like some help with understanding the formula - it's a bit confusing for me as it is
1) What is the meaning of 20*logf and 20*logd
2) What is the significance of the 20*
3) How would I calculate this on a calculator
The Revision slide for reference
Lp = 36.6 + (20*log10(F)) + (20 log10(D))
Lp = free-space path loss between antennas (in dB)
F = frequency in MHz
D = path length in miles
statistics logarithms computer-science
asked Dec 19 '18 at 19:02
KaleKale
52
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add a comment |
$begingroup$
I don't have a strong mathematical understanding of logarithms so I would like some help with understanding the formula - it's a bit confusing for me as it is
1) What is the meaning of 20*logf and 20*logd
2) What is the significance of the 20*
3) How would I calculate this on a calculator
The Revision slide for reference
Lp = 36.6 + (20*log10(F)) + (20 log10(D))
Lp = free-space path loss between antennas (in dB)
F = frequency in MHz
D = path length in miles
statistics logarithms computer-science
asked Dec 19 '18 at 19:02
KaleKale
52
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$begingroup$
I take them to mean $log{f}$ and $log{d}$
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– saulspatz
Dec 19 '18 at 20:08
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"$20 *$" means "$20 times$" (= 20 times what follows). "20 stars" would also be eligible in this Xmas time...
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– Jean Marie
Dec 19 '18 at 20:59
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Using the fact that $log a + log b = log ab$, the easiest way to enter this on your calculator is to type the value of f, $*$, the value of d, $=$. Then $log$ (I'm not sure what base this log is supposed to be with respect to, you may have adjust) and $=$ again. Then multiply by $20$ (and $=$ again). Finally, add 36.6 and hit $=$. This order will save you from any difficulties coming from calculators not always respecting order of operations in the way you expect them to.It also saves you a few keystrokes.
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– Aaron
Dec 20 '18 at 3:18
add a comment |
$begingroup$
I don't have a strong mathematical understanding of logarithms so I would like some help with understanding the formula - it's a bit confusing for me as it is
1) What is the meaning of 20*logf and 20*logd
2) What is the significance of the 20*
3) How would I calculate this on a calculator
The Revision slide for reference
Lp = 36.6 + (20*log10(F)) + (20 log10(D))
Lp = free-space path loss between antennas (in dB)
F = frequency in MHz
D = path length in miles
statistics logarithms computer-science
asked Dec 19 '18 at 19:02
KaleKale
52
$endgroup$
I don't have a strong mathematical understanding of logarithms so I would like some help with understanding the formula - it's a bit confusing for me as it is
1) What is the meaning of 20*logf and 20*logd
2) What is the significance of the 20*
3) How would I calculate this on a calculator
The Revision slide for reference
Lp = 36.6 + (20*log10(F)) + (20 log10(D))
Lp = free-space path loss between antennas (in dB)
F = frequency in MHz
D = path length in miles
statistics logarithms computer-science
statistics logarithms computer-science
asked Dec 19 '18 at 19:02
KaleKale
52
asked Dec 19 '18 at 19:02
KaleKale
52
edited Dec 20 '18 at 14:06
Kale
asked Dec 19 '18 at 19:02
KaleKale
52
asked Dec 19 '18 at 19:02
KaleKale
52
asked Dec 19 '18 at 19:02
KaleKale
52
52
$begingroup$
I take them to mean $log{f}$ and $log{d}$
$endgroup$
– saulspatz
Dec 19 '18 at 20:08
$begingroup$
"$20 *$" means "$20 times$" (= 20 times what follows). "20 stars" would also be eligible in this Xmas time...
$endgroup$
– Jean Marie
Dec 19 '18 at 20:59
$begingroup$
Using the fact that $log a + log b = log ab$, the easiest way to enter this on your calculator is to type the value of f, $*$, the value of d, $=$. Then $log$ (I'm not sure what base this log is supposed to be with respect to, you may have adjust) and $=$ again. Then multiply by $20$ (and $=$ again). Finally, add 36.6 and hit $=$. This order will save you from any difficulties coming from calculators not always respecting order of operations in the way you expect them to.It also saves you a few keystrokes.
$endgroup$
– Aaron
Dec 20 '18 at 3:18
add a comment |
$begingroup$
I take them to mean $log{f}$ and $log{d}$
$endgroup$
– saulspatz
Dec 19 '18 at 20:08
$begingroup$
"$20 *$" means "$20 times$" (= 20 times what follows). "20 stars" would also be eligible in this Xmas time...
$endgroup$
– Jean Marie
Dec 19 '18 at 20:59
$begingroup$
Using the fact that $log a + log b = log ab$, the easiest way to enter this on your calculator is to type the value of f, $*$, the value of d, $=$. Then $log$ (I'm not sure what base this log is supposed to be with respect to, you may have adjust) and $=$ again. Then multiply by $20$ (and $=$ again). Finally, add 36.6 and hit $=$. This order will save you from any difficulties coming from calculators not always respecting order of operations in the way you expect them to.It also saves you a few keystrokes.
$endgroup$
– Aaron
Dec 20 '18 at 3:18
$begingroup$
I take them to mean $log{f}$ and $log{d}$
$endgroup$
– saulspatz
Dec 19 '18 at 20:08
$begingroup$
I take them to mean $log{f}$ and $log{d}$
$endgroup$
– saulspatz
Dec 19 '18 at 20:08
$begingroup$
"$20 *$" means "$20 times$" (= 20 times what follows). "20 stars" would also be eligible in this Xmas time...
$endgroup$
– Jean Marie
Dec 19 '18 at 20:59
$begingroup$
"$20 *$" means "$20 times$" (= 20 times what follows). "20 stars" would also be eligible in this Xmas time...
$endgroup$
– Jean Marie
Dec 19 '18 at 20:59
$begingroup$
Using the fact that $log a + log b = log ab$, the easiest way to enter this on your calculator is to type the value of f, $*$, the value of d, $=$. Then $log$ (I'm not sure what base this log is supposed to be with respect to, you may have adjust) and $=$ again. Then multiply by $20$ (and $=$ again). Finally, add 36.6 and hit $=$. This order will save you from any difficulties coming from calculators not always respecting order of operations in the way you expect them to.It also saves you a few keystrokes.
$endgroup$
– Aaron
Dec 20 '18 at 3:18
$begingroup$
Using the fact that $log a + log b = log ab$, the easiest way to enter this on your calculator is to type the value of f, $*$, the value of d, $=$. Then $log$ (I'm not sure what base this log is supposed to be with respect to, you may have adjust) and $=$ again. Then multiply by $20$ (and $=$ again). Finally, add 36.6 and hit $=$. This order will save you from any difficulties coming from calculators not always respecting order of operations in the way you expect them to.It also saves you a few keystrokes.
$endgroup$
– Aaron
Dec 20 '18 at 3:18
add a comment |
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$begingroup$
I take them to mean $log{f}$ and $log{d}$
$endgroup$
– saulspatz
Dec 19 '18 at 20:08
$begingroup$
"$20 *$" means "$20 times$" (= 20 times what follows). "20 stars" would also be eligible in this Xmas time...
$endgroup$
– Jean Marie
Dec 19 '18 at 20:59
$begingroup$
Using the fact that $log a + log b = log ab$, the easiest way to enter this on your calculator is to type the value of f, $*$, the value of d, $=$. Then $log$ (I'm not sure what base this log is supposed to be with respect to, you may have adjust) and $=$ again. Then multiply by $20$ (and $=$ again). Finally, add 36.6 and hit $=$. This order will save you from any difficulties coming from calculators not always respecting order of operations in the way you expect them to.It also saves you a few keystrokes.
$endgroup$
– Aaron
Dec 20 '18 at 3:18