> Jerry just typed Q?. Can everyone see that properly as Q^2? I ask,
> of course, because I'm tired of typing ^2, and would rather use ? if
> it works widely.
I've always wondered why I^2C (inter-integrated circuit) was ASCIIfied
as I2C and not IIC. If you're sick of Q^2 could you not write QQ?
Tin seems to have stripped the character incoming, and wants to strip it
again outgoing. I can't be bothered fixing it, though.
Reply by Matt Timmermans●December 24, 20032003-12-24
"robert bristow-johnson" <rbj@surfglobal.net> wrote in message
news:BC0E7D7C.7293%rbj@surfglobal.net...
> don't count me in. Q� looks more like "Q double prime" or the second
> derivative of Q. why is "^2" so hard? 'specially when MATLAB uses it.
> (and some other language that i forgot. was it Basic?)
It's more compact, and less ambiguous, so I can write 5a�b+2ab� instead of
5*(a^2)*b + 2*a*(b^2). I guess you can't see it because you're using a Mac,
and Mac's don't have that character in their native 8-bit character set. I
would expect your news reader to display it properly anyway, but I guess
that feature didn't make it onto the priority list when they ported OE from
Windows.
Reply by Matt Timmermans●December 24, 20032003-12-24
"Rune Allnor" <allnor@tele.ntnu.no> wrote in message
news:f56893ae.0312240043.3e8833a5@posting.google.com...
> I can see that as sqr(Q), yes. What kind of voodoo did you perform to
> write that? Is is something with you newsreader or is it something
> with windows?
I hold ALT and type 0178. It's a standard character (code point 178) in the
ISO-8859-1 (ISO-Latin-1) or Unicode character sets, but it's not really
commonly used, so proprietary character sets that keep the accented
characters from 8859-1 might replace it with something else. R b-j seems to
have a right-double-quote there, for example.
Reply by Jerry Avins●December 24, 20032003-12-24
Rune Allnor wrote:
> "Matt Timmermans" <mt0000@sympatico.nospam-remove.ca> wrote in message news:<Dk7Gb.7859$d%1.1784533@news20.bellglobal.com>...
>
>>Jerry just typed Q�. Can everyone see that properly as Q^2? I ask, of
>>course, because I'm tired of typing ^2, and would rather use � if it works
>>widely.
>
>
> I can see that as sqr(Q), yes. What kind of voodoo did you perform to
> write that? Is is something with you newsreader or is it something
> with windows?
>
> [Before you flame me, I've only used windows for the last couple of
> years. Before that I used various UNIX flavours, and learned the
> hard way to avoid "funny" characters, like some that go into the
> various Scandinavian alphabets.]
>
> Rune
Robert: I will reform. It's part of all fixed-width fonts I know, and I
fell into the Fallacy of Universality. (I just made that up.)
Rune: There is in Windows a program called "Character Map", the
equivalent of "Key Caps" on a Mac. In XP, it's under Start; All
Programs; Accessories; System Tools. (I keep a shortcut to it.)
Jerry
--
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������
Reply by Rune Allnor●December 24, 20032003-12-24
"Matt Timmermans" <mt0000@sympatico.nospam-remove.ca> wrote in message news:<Dk7Gb.7859$d%1.1784533@news20.bellglobal.com>...
> Jerry just typed Q�. Can everyone see that properly as Q^2? I ask, of
> course, because I'm tired of typing ^2, and would rather use � if it works
> widely.
I can see that as sqr(Q), yes. What kind of voodoo did you perform to
write that? Is is something with you newsreader or is it something
with windows?
[Before you flame me, I've only used windows for the last couple of
years. Before that I used various UNIX flavours, and learned the
hard way to avoid "funny" characters, like some that go into the
various Scandinavian alphabets.]
Rune
Reply by robert bristow-johnson●December 24, 20032003-12-24
In article Dk7Gb.7859$d%1.1784533@news20.bellglobal.com, Matt Timmermans at
mt0000@sympatico.nospam-remove.ca wrote on 12/23/2003 22:02:
> Jerry just typed Q�. Can everyone see that properly as Q^2? I ask, of
> course, because I'm tired of typing ^2, and would rather use � if it works
> widely.
don't count me in. Q� looks more like "Q double prime" or the second
derivative of Q. why is "^2" so hard? 'specially when MATLAB uses it.
(and some other language that i forgot. was it Basic?)
whatever.
r b-j
Reply by Matt Timmermans●December 23, 20032003-12-23
Jerry just typed Q�. Can everyone see that properly as Q^2? I ask, of
course, because I'm tired of typing ^2, and would rather use � if it works
widely.
Reply by Jerry Avins●December 23, 20032003-12-23
Dilip V. Sarwate wrote:
> "Parthasarathy" <parth175@yahoo.co.in> asked in message
> news:7f126353.0312230103.680fb470@posting.google.com...
>
>>Hi
>>
>> I am using QPSK Modulation. I believe to perform
>>carrier synchronisation at the receiver, we need to also
>>have the carrier component in the received signal. How
>>do we achieve this?
>
>
> The square of a QPSK signal is a BPSK signal
> at twice the carrier frequency (plus a DC component).
> The square of this BPSK signal is an unmodulated tone
> at four times the carrier frequency. This can be used for
> synchronization. However, keep in mind that there will be
> a four-fold phase ambiguity, which can cause (I, Q) to be
> demodulated into (Q, -I), (-I, -Q) or (-Q, I) instead of the
> desired (I, Q). The phase ambiguity can be resolved by
> differential encoding and decoding of the *complex*
> data symbols (i.e., binary differential encoding of
> the I and Q data streams separately does not work.)
>
> Hope this helps.
Someone with only a little more understanding than Radium insists (in
private correspondence) that I and Q channels can be distinguished by
squaring them. The Q� channel, he claims, has a negative DC component.
Jerry
--
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������
Reply by ●December 23, 20032003-12-23
"Parthasarathy" <parth175@yahoo.co.in> asked in message
news:7f126353.0312230103.680fb470@posting.google.com...
> Hi
>
> I am using QPSK Modulation. I believe to perform
> carrier synchronisation at the receiver, we need to also
> have the carrier component in the received signal. How
> do we achieve this?
The square of a QPSK signal is a BPSK signal
at twice the carrier frequency (plus a DC component).
The square of this BPSK signal is an unmodulated tone
at four times the carrier frequency. This can be used for
synchronization. However, keep in mind that there will be
a four-fold phase ambiguity, which can cause (I, Q) to be
demodulated into (Q, -I), (-I, -Q) or (-Q, I) instead of the
desired (I, Q). The phase ambiguity can be resolved by
differential encoding and decoding of the *complex*
data symbols (i.e., binary differential encoding of
the I and Q data streams separately does not work.)
Hope this helps.
Reply by Parthasarathy●December 23, 20032003-12-23
Hi
I am using QPSK Modulation. Say the data rate be 'Rb' and the
carrier frequency is 'fc'.
I believe to perform carrier synchronisation at the receiver, we
need to also have the carrier component in the received signal. How do
we achieve this?
Thanks in advance
Bye