<s>
Very	B-Device
minimum	I-Device
shift	I-Device
keying	I-Device
,	O
or	O
VMSK	B-Device
,	O
modulation	B-Application
,	O
is	O
one	O
of	O
several	O
ultra-narrow-band	O
modulation	B-Application
(	O
UNBM	O
)	O
methods	O
indeterminately	O
claimed	O
to	O
send	O
high-speed	O
digital	O
data	O
through	O
very	O
low	O
bandwidth	B-Algorithm
(	O
or	O
narrowband	O
)	O
channels	O
.	O
</s>
<s>
VMSK	B-Device
is	O
a	O
type	O
of	O
phase-shift	B-General_Concept
keying	I-General_Concept
,	O
not	O
related	O
to	O
minimum	B-Device
shift	I-Device
keying	I-Device
.	O
</s>
<s>
VMSK	B-Device
was	O
introduced	O
in	O
1998	O
as	O
a	O
cellular	O
telephone	O
modulating	O
method	O
.	O
</s>
<s>
There	O
have	O
been	O
individuals	O
who	O
have	O
made	O
an	O
analysis	O
based	O
on	O
positive	O
group	O
delay	O
filters	O
that	O
claim	O
the	O
method	O
does	O
not	O
work	O
;	O
however	O
,	O
VMSK	B-Device
,	O
like	O
all	O
ultra-narrow	O
band	O
modulation	B-Application
methods	O
uses	O
negative	O
-	O
or	O
zero-delay	O
filters	O
.	O
</s>
<s>
Walker	O
claims	O
that	O
with	O
VMSK	B-Device
,	O
"	O
Efficiencies	O
up	O
to	O
15	O
bits/s/Hz	B-Protocol
are	O
now	O
being	O
achieved	O
in	O
usable	O
hardware	O
with	O
C/N	O
ratios	O
better	O
than	O
that	O
obtainable	O
using	O
FM	O
,	O
BPSK	O
or	O
QPSK.	O
"	O
</s>
<s>
Analysis	O
by	O
third	O
parties	O
(	O
Karn	O
and	O
Tomasic	O
)	O
have	O
concluded	O
that	O
"	O
no	O
ultra	O
narrow	O
band	O
modulation	B-Application
(	O
UNBM	O
)	O
method	O
,	O
which	O
includes	O
very	B-Device
minimum	I-Device
shift	I-Device
keying	I-Device
(	O
VMSK	B-Device
)	O
and	O
VPSK	O
,	O
can	O
have	O
substantially	O
greater	O
efficiency	O
than	O
conventional	O
methods.	O
"	O
</s>
<s>
On	O
a	O
spectrum	O
analyzer	O
,	O
a	O
VMSK	B-Device
signal	O
looks	O
narrow	O
.	O
</s>
<s>
However	O
,	O
the	O
actual	O
bandwidth	B-Algorithm
required	O
to	O
avoid	O
interference	O
is	O
much	O
wider	O
.	O
</s>
<s>
One	O
analyst	O
says	O
"	O
the	O
spectral	B-Protocol
efficiency	I-Protocol
claims	O
being	O
made	O
for	O
VMSK	B-Device
are	O
hogwash	O
"	O
,	O
regardless	O
of	O
the	O
filter	O
used	O
.	O
</s>
<s>
VMSK	B-Device
is	O
promoted	O
primarily	O
by	O
H	O
.	O
R	O
.	O
Walker	O
,	O
owner	O
of	O
the	O
"	O
Welcome	O
to	O
the	O
Ultra	O
Narrowband	O
Club	O
"	O
website	O
,	O
and	O
author	O
of	O
several	O
papers	O
and	O
publications	O
on	O
the	O
arguments	O
.	O
</s>
<s>
It	O
was	O
reported	O
in	O
2000	O
that	O
"	O
AlphaCom	O
Communications	O
holds	O
patent	O
rights	O
to	O
the	O
non-Nyquist	O
filters	O
and	O
other	O
aspects	O
of	O
VMSK	B-Device
and	O
VMSK/2	B-Device
technology	O
.	O
</s>
<s>
A	O
2003	O
Securities	O
and	O
Exchange	O
Commission	O
charge	O
against	O
AlphaCom	O
and	O
its	O
principals	O
alleges	O
that	O
"	O
defendants	O
raised	O
these	O
funds	O
by	O
falsely	O
representing	O
that	O
AlphaCom	O
owned	O
exclusive	O
rights	O
to	O
novel	O
Internet	O
technologies	O
,	O
Network	O
Utilities	O
(	O
NU	O
)	O
and	O
Very	O
Minimal	O
Shift	O
Keying	O
(	O
VMSK	B-Device
)	O
,	O
that	O
were	O
supposed	O
to	O
increase	O
Internet	O
downloading	O
speeds	O
and	O
the	O
speed	O
of	O
access	O
to	O
the	O
Internet	O
.	O
</s>
<s>
In	O
order	O
to	O
avoid	O
further	O
legal	O
costs	O
,	O
Walker	O
agreed	O
to	O
surrender	O
the	O
ownership	O
of	O
the	O
VMSK	B-Device
patents	O
US	O
5,930,303	O
and	O
US	O
6,748,022	O
to	O
AlphaCom	O
in	O
return	O
for	O
AlphaCom	O
making	O
no	O
further	O
claims	O
against	O
Walker	O
or	O
Pegasus	O
regarding	O
any	O
newer	O
methods	O
.	O
</s>
<s>
In	O
2007	O
,	O
Compress	O
Technologies	O
,	O
Inc.	O
,	O
announced	O
on	O
their	O
web	O
site	O
that	O
they	O
had	O
"	O
acquired	O
VMSK	B-Device
Technology.	O
"	O
</s>
