On Tuesday, October 29, 2013 10:21:33 PM UTC-7, Eric Jacobsen wrote:
> On Tue, 29 Oct 2013 21:47:54 -0700 (PDT), Verictor
>
> <stehuang@gmail.com> wrote:
>
>
>
> >On Tuesday, October 29, 2013 2:33:13 PM UTC-4, Eric Jacobsen wrote:
>
> >> On Tue, 29 Oct 2013 10:31:44 -0700 (PDT), Verictor
>
> >>=20
>
> >> <stehuang@gmail.com> wrote:
>
> >>=20
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> >>=20
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> >>=20
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> >> >On Sunday, October 27, 2013 1:02:07 AM UTC-7, Eric Jacobsen wrote:
>
> >>=20
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> >> >> On Sat, 26 Oct 2013 14:18:09 -0700 (PDT), Verictor
>
> >>=20
>
> >> >>=3D20
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> >>=20
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> >> >> <stehuang@gmail.com> wrote:
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >>=3D20
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> >> >>=3D20
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> >>=20
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> >> >> >Hi,
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >> >
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >> >Anyone is aware of state search algorithms in MLSE (maximum likelihoo=
>
> >d s=3D
>
> >>=20
>
> >> >equence equalization) other than the Viterbi?
>
> >>=20
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> >> >>=3D20
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> >>=20
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> >> >> >
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >> >Thanks
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >> Sequential decoder?
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >>=3D20
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> >> >>=3D20
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> >> >> Can I ask why you think you need MLSE?
>
> >>=20
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> >> >>=3D20
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >>=3D20
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> >> >>=3D20
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> >>=20
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> >> >> Eric Jacobsen
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> >>=20
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> >> >>=3D20
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> >>=20
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> >> >> Anchor Hill Communications
>
> >>=20
>
> >> >>=3D20
>
> >>=20
>
> >> >> http://www.anchorhill.com
>
> >>=20
>
> >> >
>
> >>=20
>
> >> >For some reason, my Group didn't get updated to see new posts.=3D20
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> >>=20
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> >> >
>
> >>=20
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> >> >Sequential decoder is used on convolutional codes, as far as I know. Can=
>
> > it=3D
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> >>=20
>
> >> > also be used on non-coded communication? In particular, combined equali=
>
> >zat=3D
>
> >>=20
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> >> >ion and maximum likelihood state estimate?
>
> >>=20
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> >>=20
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> >>=20
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> >> It's possible, but sequential decoding is used primarily when a long
>
> >>=20
>
> >> constraint length can be tolerated in favor of better performance.
>
> >>=20
>
> >> Modulation-based trellis patterns tend to be short, which favors the
>
> >>=20
>
> >> Viterbi algorithm.
>
> >>=20
>
> >>=20
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> >>=20
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> >> > I was referring to channel estim=3D
>
> >>=20
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> >> >ate along with incoming sequence detection.
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> >>=20
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> >>=20
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> >>=20
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> >> Soft-input sequential decoders exist.
>
> >>=20
>
> >
>
> >I've never actually implemented a SISO sequential decoders. Dosn't soft seq=
>
> >uential decoder become more complex so that it loss its advantage of simple=
>
> >r implementation complexity? I think some texts say sequential decoder is u=
>
> >sually hard decoder. There are second opinions on this?
>
>
>
> Soft-input sequential decoders have been around a long time and are
>
> generally of lower complexity than (or comparable complexity to,
>
> depending on constraint lengths) a typical soft-input Viterbi decoder.
>
>
>
>
>
> But I was mostly thinking of detection or decoding rather than an MLSE
>
> Equalizer (brain fart on my part, as you did say equalizer). A MAP
>
> decoder (aka APP decoder) is not an MLSE, but it can be used for
>
> equalization in the same manner as a Viterbi algorithm, or joint
>
> channel estimation and equalization.
>
>
>
> I doubt a sequential decoder would be desirable for channel estimation
>
> or equalization unless the channel delay spread covered a large number
>
> of symbols, i.e., the equalizer was hugely complex. So, probably not
>
> practical.
>
That is a candid suggestion. When I asked, I was thinking other ways to do VA. Thanks anyway.
>
> >>=20
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> >>=20
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> >> > There may be ways to incorporat=3D
>
> >>=20
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> >> >e CIR estimate in the sequential decoder (or someone had done that alrea=
>
> >dy =3D
>
> >>=20
>
> >> >but I don't know). I was asking to see if someone knows new techniques t=
>
> >o m=3D
>
> >>=20
>
> >> >inimize the search.=3D20
>
> >>=20
>
> >> >
>
> >>=20
>
> >> >Why need MLSE? I think a sequence base, not symbol-by-symbol, approach i=
>
> >s o=3D
>
> >>=20
>
> >> >ptimal as intuitively, we have more degree of information.=3D20
>
> >>=20
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> >> >
>
> >>=20
>
> >> >Thanks
>
> >>=20
>
> >>=20
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> >>=20
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> >>=20
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> >>=20
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> >>=20
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> >>=20
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> >> Eric Jacobsen
>
> >>=20
>
> >> Anchor Hill Communications
>
> >>=20
>
> >> http://www.anchorhill.com
>
> >
>
>
>
> Eric Jacobsen
>
> Anchor Hill Communications
>
> http://www.anchorhill.com
Reply by Eric Jacobsen●October 30, 20132013-10-30
On Tue, 29 Oct 2013 21:47:54 -0700 (PDT), Verictor
<stehuang@gmail.com> wrote:
>On Tuesday, October 29, 2013 2:33:13 PM UTC-4, Eric Jacobsen wrote:
>> On Tue, 29 Oct 2013 10:31:44 -0700 (PDT), Verictor
>>=20
>> <stehuang@gmail.com> wrote:
>>=20
>>=20
>>=20
>> >On Sunday, October 27, 2013 1:02:07 AM UTC-7, Eric Jacobsen wrote:
>>=20
>> >> On Sat, 26 Oct 2013 14:18:09 -0700 (PDT), Verictor
>>=20
>> >>=3D20
>>=20
>> >> <stehuang@gmail.com> wrote:
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >> >Hi,
>>=20
>> >>=3D20
>>=20
>> >> >
>>=20
>> >>=3D20
>>=20
>> >> >Anyone is aware of state search algorithms in MLSE (maximum likelihoo=
>d s=3D
>>=20
>> >equence equalization) other than the Viterbi?
>>=20
>> >>=3D20
>>=20
>> >> >
>>=20
>> >>=3D20
>>=20
>> >> >Thanks
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >> Sequential decoder?
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >> Can I ask why you think you need MLSE?
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >>=3D20
>>=20
>> >> Eric Jacobsen
>>=20
>> >>=3D20
>>=20
>> >> Anchor Hill Communications
>>=20
>> >>=3D20
>>=20
>> >> http://www.anchorhill.com
>>=20
>> >
>>=20
>> >For some reason, my Group didn't get updated to see new posts.=3D20
>>=20
>> >
>>=20
>> >Sequential decoder is used on convolutional codes, as far as I know. Can=
> it=3D
>>=20
>> > also be used on non-coded communication? In particular, combined equali=
>zat=3D
>>=20
>> >ion and maximum likelihood state estimate?
>>=20
>>=20
>>=20
>> It's possible, but sequential decoding is used primarily when a long
>>=20
>> constraint length can be tolerated in favor of better performance.
>>=20
>> Modulation-based trellis patterns tend to be short, which favors the
>>=20
>> Viterbi algorithm.
>>=20
>>=20
>>=20
>> > I was referring to channel estim=3D
>>=20
>> >ate along with incoming sequence detection.
>>=20
>>=20
>>=20
>> Soft-input sequential decoders exist.
>>=20
>
>I've never actually implemented a SISO sequential decoders. Dosn't soft seq=
>uential decoder become more complex so that it loss its advantage of simple=
>r implementation complexity? I think some texts say sequential decoder is u=
>sually hard decoder. There are second opinions on this?
Soft-input sequential decoders have been around a long time and are
generally of lower complexity than (or comparable complexity to,
depending on constraint lengths) a typical soft-input Viterbi decoder.
But I was mostly thinking of detection or decoding rather than an MLSE
Equalizer (brain fart on my part, as you did say equalizer). A MAP
decoder (aka APP decoder) is not an MLSE, but it can be used for
equalization in the same manner as a Viterbi algorithm, or joint
channel estimation and equalization.
I doubt a sequential decoder would be desirable for channel estimation
or equalization unless the channel delay spread covered a large number
of symbols, i.e., the equalizer was hugely complex. So, probably not
practical.
>>=20
>>=20
>> > There may be ways to incorporat=3D
>>=20
>> >e CIR estimate in the sequential decoder (or someone had done that alrea=
>dy =3D
>>=20
>> >but I don't know). I was asking to see if someone knows new techniques t=
>o m=3D
>>=20
>> >inimize the search.=3D20
>>=20
>> >
>>=20
>> >Why need MLSE? I think a sequence base, not symbol-by-symbol, approach i=
>s o=3D
>>=20
>> >ptimal as intuitively, we have more degree of information.=3D20
>>=20
>> >
>>=20
>> >Thanks
>>=20
>>=20
>>=20
>>=20
>>=20
>>=20
>>=20
>> Eric Jacobsen
>>=20
>> Anchor Hill Communications
>>=20
>> http://www.anchorhill.com
>
On Tuesday, October 29, 2013 2:33:13 PM UTC-4, Eric Jacobsen wrote:
> On Tue, 29 Oct 2013 10:31:44 -0700 (PDT), Verictor
>
> <stehuang@gmail.com> wrote:
>
>
>
> >On Sunday, October 27, 2013 1:02:07 AM UTC-7, Eric Jacobsen wrote:
>
> >> On Sat, 26 Oct 2013 14:18:09 -0700 (PDT), Verictor
>
> >>=20
>
> >> <stehuang@gmail.com> wrote:
>
> >>=20
>
> >>=20
>
> >>=20
>
> >> >Hi,
>
> >>=20
>
> >> >
>
> >>=20
>
> >> >Anyone is aware of state search algorithms in MLSE (maximum likelihood s=
>
> >equence equalization) other than the Viterbi?
>
> >>=20
>
> >> >
>
> >>=20
>
> >> >Thanks
>
> >>=20
>
> >>=20
>
> >>=20
>
> >> Sequential decoder?
>
> >>=20
>
> >>=20
>
> >>=20
>
> >> Can I ask why you think you need MLSE?
>
> >>=20
>
> >>=20
>
> >>=20
>
> >>=20
>
> >>=20
>
> >> Eric Jacobsen
>
> >>=20
>
> >> Anchor Hill Communications
>
> >>=20
>
> >> http://www.anchorhill.com
>
> >
>
> >For some reason, my Group didn't get updated to see new posts.=20
>
> >
>
> >Sequential decoder is used on convolutional codes, as far as I know. Can it=
>
> > also be used on non-coded communication? In particular, combined equalizat=
>
> >ion and maximum likelihood state estimate?
>
>
>
> It's possible, but sequential decoding is used primarily when a long
>
> constraint length can be tolerated in favor of better performance.
>
> Modulation-based trellis patterns tend to be short, which favors the
>
> Viterbi algorithm.
>
>
>
> > I was referring to channel estim=
>
> >ate along with incoming sequence detection.
>
>
>
> Soft-input sequential decoders exist.
>
I've never actually implemented a SISO sequential decoders. Dosn't soft sequential decoder become more complex so that it loss its advantage of simpler implementation complexity? I think some texts say sequential decoder is usually hard decoder. There are second opinions on this?
>
>
> > There may be ways to incorporat=
>
> >e CIR estimate in the sequential decoder (or someone had done that already =
>
> >but I don't know). I was asking to see if someone knows new techniques to m=
>
> >inimize the search.=20
>
> >
>
> >Why need MLSE? I think a sequence base, not symbol-by-symbol, approach is o=
>
> >ptimal as intuitively, we have more degree of information.=20
>
> >
>
> >Thanks
>
>
>
>
>
>
>
> Eric Jacobsen
>
> Anchor Hill Communications
>
> http://www.anchorhill.com
Reply by Eric Jacobsen●October 29, 20132013-10-29
On Tue, 29 Oct 2013 10:31:44 -0700 (PDT), Verictor
<stehuang@gmail.com> wrote:
>On Sunday, October 27, 2013 1:02:07 AM UTC-7, Eric Jacobsen wrote:
>> On Sat, 26 Oct 2013 14:18:09 -0700 (PDT), Verictor
>>=20
>> <stehuang@gmail.com> wrote:
>>=20
>>=20
>>=20
>> >Hi,
>>=20
>> >
>>=20
>> >Anyone is aware of state search algorithms in MLSE (maximum likelihood s=
>equence equalization) other than the Viterbi?
>>=20
>> >
>>=20
>> >Thanks
>>=20
>>=20
>>=20
>> Sequential decoder?
>>=20
>>=20
>>=20
>> Can I ask why you think you need MLSE?
>>=20
>>=20
>>=20
>>=20
>>=20
>> Eric Jacobsen
>>=20
>> Anchor Hill Communications
>>=20
>> http://www.anchorhill.com
>
>For some reason, my Group didn't get updated to see new posts.=20
>
>Sequential decoder is used on convolutional codes, as far as I know. Can it=
> also be used on non-coded communication? In particular, combined equalizat=
>ion and maximum likelihood state estimate?
It's possible, but sequential decoding is used primarily when a long
constraint length can be tolerated in favor of better performance.
Modulation-based trellis patterns tend to be short, which favors the
Viterbi algorithm.
> I was referring to channel estim=
>ate along with incoming sequence detection.
Soft-input sequential decoders exist.
> There may be ways to incorporat=
>e CIR estimate in the sequential decoder (or someone had done that already =
>but I don't know). I was asking to see if someone knows new techniques to m=
>inimize the search.=20
>
>Why need MLSE? I think a sequence base, not symbol-by-symbol, approach is o=
>ptimal as intuitively, we have more degree of information.=20
>
>Thanks
On Sunday, October 27, 2013 1:02:07 AM UTC-7, Eric Jacobsen wrote:
> On Sat, 26 Oct 2013 14:18:09 -0700 (PDT), Verictor
>
> <stehuang@gmail.com> wrote:
>
>
>
> >Hi,
>
> >
>
> >Anyone is aware of state search algorithms in MLSE (maximum likelihood sequence equalization) other than the Viterbi?
>
> >
>
> >Thanks
>
>
>
> Sequential decoder?
>
>
>
> Can I ask why you think you need MLSE?
>
>
>
>
>
> Eric Jacobsen
>
> Anchor Hill Communications
>
> http://www.anchorhill.com
For some reason, my Group didn't get updated to see new posts.
Sequential decoder is used on convolutional codes, as far as I know. Can it also be used on non-coded communication? In particular, combined equalization and maximum likelihood state estimate? I was referring to channel estimate along with incoming sequence detection. There may be ways to incorporate CIR estimate in the sequential decoder (or someone had done that already but I don't know). I was asking to see if someone knows new techniques to minimize the search.
Why need MLSE? I think a sequence base, not symbol-by-symbol, approach is optimal as intuitively, we have more degree of information.
Thanks
Reply by Eric Jacobsen●October 27, 20132013-10-27
On Sat, 26 Oct 2013 14:18:09 -0700 (PDT), Verictor
<stehuang@gmail.com> wrote:
>Hi,
>
>Anyone is aware of state search algorithms in MLSE (maximum likelihood sequence equalization) other than the Viterbi?
>
>Thanks
Sequential decoder?
Can I ask why you think you need MLSE?
Eric Jacobsen
Anchor Hill Communications
http://www.anchorhill.com
Reply by Verictor●October 26, 20132013-10-26
Hi,
Anyone is aware of state search algorithms in MLSE (maximum likelihood sequence equalization) other than the Viterbi?
Thanks