Sign in
Search matlab
Subscribe to matlab
matlab by Keywords
Atanh | Autocorrelation | Bandpass Filter | C++ | Conv | Database | Deconv | Excel | FFT | Filter | Filtering | FIR | Fourier Transfrom | FSK | Gaussian Noise | Haykin | IFFT | Image | Java | LFSR | LMS | LPC | MEX | OFDM | QPSK | Radix | Random | Sampling | Segmentation | Simulink | Visual Basic | Waveform | Wavelet
Discussion Groups
Discussion Groups | Matlab DSP | Pseudo-random sequence and pilots in OFDM
Technical discussion about Matlab and issues related to Digital Signal Processing.
Pseudo-random sequence and pilots in OFDM - vcteo - Nov 22 20:26:00 2005
Hi, i'm doing a project on OFDM and currently i'm just playing around
and exploring with the HiperLan/2 demo that comes together with Simulink.
I noticed at OFDM transmission, pilots are inserted and these pilots
are single sample datas inserted regularly btwn the actual data. These
pilots are generated by a Pseudo-random binary generator block.
What is this block? What is the theory behind it? And why do we use
this block to generate the pilots?
(You need to be a member of matlab -- send a blank email to matlab-subscribe@yahoogroups.com )
Re: Pseudo-random sequence and pilots in OFDM - Sameer S.M - Nov 27 23:43:00 2005
Hello,
Pilot signals are inserted in between (or at the beginning) of data samples
to aid channel estimation, synchronization and equalization. Mostly these
procedures requires the computation of auto and cross correlations of the
pilot samples. As PN sequences have good auto/cross correlation properties,
they are the simplest choices for pilot sequences.
bye
Sameer On 11/23/05, vcteo <vcteo@vcte...> wrote:
>
> Hi, i'm doing a project on OFDM and currently i'm just playing around
> and exploring with the HiperLan/2 demo that comes together with Simulink.
>
> I noticed at OFDM transmission, pilots are inserted and these pilots
> are single sample datas inserted regularly btwn the actual data. These
> pilots are generated by a Pseudo-random binary generator block.
>
> What is this block? What is the theory behind it? And why do we use
> this block to generate the pilots?
(You need to be a member of matlab -- send a blank email to matlab-subscribe@yahoogroups.com )
Pilot signals are inserted in between (or at the beginning) of data samples
to aid channel estimation, synchronization and equalization. Mostly these
procedures requires the computation of auto and cross correlations of the
pilot samples. As PN sequences have good auto/cross correlation properties,
they are the simplest choices for pilot sequences.
bye
Sameer On 11/23/05, vcteo <vcteo@vcte...> wrote:
>
> Hi, i'm doing a project on OFDM and currently i'm just playing around
> and exploring with the HiperLan/2 demo that comes together with Simulink.
>
> I noticed at OFDM transmission, pilots are inserted and these pilots
> are single sample datas inserted regularly btwn the actual data. These
> pilots are generated by a Pseudo-random binary generator block.
>
> What is this block? What is the theory behind it? And why do we use
> this block to generate the pilots?
(You need to be a member of matlab -- send a blank email to matlab-subscribe@yahoogroups.com )
Re: Pseudo-random sequence and pilots in OFDM - Vincent Teo - Nov 28 1:05:00 2005
Thx, regarding the PN sequence. They are only quasi-random bits generated by an algorithm
right?
So, if they are just bits of 1 or -1 what makes them possess such correlation properties? Is it the combination of the bits that create such properties?
"Sameer S.M" <sameerece@same...> wrote: Hello,
Pilot signals are inserted in between (or at the beginning) of data samples to aid channel estimation, synchronization and equalization. Mostly these procedures requires the computation of auto and cross correlations of the pilot samples. As PN sequences have good auto/cross correlation properties, they are the simplest choices for pilot sequences.
bye
Sameer On 11/23/05, vcteo <vcteo@vcte...> wrote: Hi, i'm doing a project on OFDM and currently i'm just playing around
and exploring with the HiperLan/2 demo that comes together with Simulink.
I noticed at OFDM transmission, pilots are inserted and these pilots
are single sample datas inserted regularly btwn the actual data. These
pilots are generated by a Pseudo-random binary generator block.
What is this block? What is the theory behind it? And why do we use
this block to generate the pilots?
(You need to be a member of matlab -- send a blank email to matlab-subscribe@yahoogroups.com )
So, if they are just bits of 1 or -1 what makes them possess such correlation properties? Is it the combination of the bits that create such properties?
"Sameer S.M" <sameerece@same...> wrote: Hello,
Pilot signals are inserted in between (or at the beginning) of data samples to aid channel estimation, synchronization and equalization. Mostly these procedures requires the computation of auto and cross correlations of the pilot samples. As PN sequences have good auto/cross correlation properties, they are the simplest choices for pilot sequences.
bye
Sameer On 11/23/05, vcteo <vcteo@vcte...> wrote: Hi, i'm doing a project on OFDM and currently i'm just playing around
and exploring with the HiperLan/2 demo that comes together with Simulink.
I noticed at OFDM transmission, pilots are inserted and these pilots
are single sample datas inserted regularly btwn the actual data. These
pilots are generated by a Pseudo-random binary generator block.
What is this block? What is the theory behind it? And why do we use
this block to generate the pilots?
(You need to be a member of matlab -- send a blank email to matlab-subscribe@yahoogroups.com )
Re: Pseudo-random sequence and pilots in OFDM - Sameer S.M - Nov 30 11:50:00 2005
hai,
Ya...u r right...Some special combinations of 1's and -1's pocesses some
wonderful correlation properties...These sequences are called Maximal Length
(ML) sequences. There are some more variants like Gold codes, Kasami codes
etc that too pocess similar properties...
bye
sameer
On 11/28/05, Vincent Teo <vcteo@vcte...> wrote:
>
> Thx, regarding the PN sequence. They are only quasi-random bits generated
> by an algorithm right?
> So, if they are just bits of 1 or -1 what makes them possess such
> correlation properties? Is it the combination of the bits that create such
> properties?
>
> *"Sameer S.M" <sameerece@same...>* wrote:
>
> Hello,
> Pilot signals are inserted in between (or at the beginning) of data
> samples to aid channel estimation, synchronization and equalization. Mostly
> these procedures requires the computation of auto and cross correlations of
> the pilot samples. As PN sequences have good auto/cross correlation
> properties, they are the simplest choices for pilot sequences.
>
> bye
> Sameer > On 11/23/05, vcteo <vcteo@vcte...> wrote:
> >
> > Hi, i'm doing a project on OFDM and currently i'm just playing around
> > and exploring with the HiperLan/2 demo that comes together with
> > Simulink.
> >
> > I noticed at OFDM transmission, pilots are inserted and these pilots
> > are single sample datas inserted regularly btwn the actual data. These
> > pilots are generated by a Pseudo-random binary generator block.
> >
> > What is this block? What is the theory behind it? And why do we use
> > this block to generate the pilots?
(You need to be a member of matlab -- send a blank email to matlab-subscribe@yahoogroups.com )
Ya...u r right...Some special combinations of 1's and -1's pocesses some
wonderful correlation properties...These sequences are called Maximal Length
(ML) sequences. There are some more variants like Gold codes, Kasami codes
etc that too pocess similar properties...
bye
sameer
On 11/28/05, Vincent Teo <vcteo@vcte...> wrote:
>
> Thx, regarding the PN sequence. They are only quasi-random bits generated
> by an algorithm right?
> So, if they are just bits of 1 or -1 what makes them possess such
> correlation properties? Is it the combination of the bits that create such
> properties?
>
> *"Sameer S.M" <sameerece@same...>* wrote:
>
> Hello,
> Pilot signals are inserted in between (or at the beginning) of data
> samples to aid channel estimation, synchronization and equalization. Mostly
> these procedures requires the computation of auto and cross correlations of
> the pilot samples. As PN sequences have good auto/cross correlation
> properties, they are the simplest choices for pilot sequences.
>
> bye
> Sameer > On 11/23/05, vcteo <vcteo@vcte...> wrote:
> >
> > Hi, i'm doing a project on OFDM and currently i'm just playing around
> > and exploring with the HiperLan/2 demo that comes together with
> > Simulink.
> >
> > I noticed at OFDM transmission, pilots are inserted and these pilots
> > are single sample datas inserted regularly btwn the actual data. These
> > pilots are generated by a Pseudo-random binary generator block.
> >
> > What is this block? What is the theory behind it? And why do we use
> > this block to generate the pilots?
(You need to be a member of matlab -- send a blank email to matlab-subscribe@yahoogroups.com )