<s>
M17	B-Device
is	O
a	O
digital	B-General_Concept
radio	O
modulation	O
mode	O
developed	O
by	O
Wojciech	O
Kaczmarski	O
(	O
amateur	O
radio	O
call	O
sign	O
SP5WWP	O
)	O
et	O
al	O
.	O
</s>
<s>
M17	B-Device
is	O
primarily	O
designed	O
for	O
voice	O
communications	O
on	O
VHF	B-Algorithm
amateur	O
radio	O
band	O
and	O
above	O
.	O
</s>
<s>
The	O
project	O
received	O
a	O
grant	O
from	O
the	O
Amateur	O
Radio	O
Digital	B-General_Concept
Communications	O
in	O
2021	O
and	O
2022	O
.	O
</s>
<s>
M17	B-Device
utilizes	O
4,800	O
symbols	O
per	O
second	O
4FSK	O
with	O
a	O
root	O
Nyquist	O
filter	O
applied	O
to	O
the	O
bitstream	O
.	O
</s>
<s>
In	O
2021	O
,	O
Kaczmarski	O
received	O
the	O
ARRL	O
Technical	O
Innovation	O
Award	O
for	O
developing	O
an	O
open-source	O
digital	B-General_Concept
radio	O
communication	O
protocol	O
,	O
leading	O
to	O
further	O
advancements	O
in	O
amateur	O
radio	O
.	O
</s>
<s>
M17	B-Device
uses	O
Codec	B-Algorithm
2	I-Algorithm
,	O
a	O
low	O
bitrate	O
voice	B-Application
codec	I-Application
developed	O
by	O
David	O
Rowe	O
VK5DGR	O
et	O
al	O
.	O
</s>
<s>
Codec	B-Algorithm
2	I-Algorithm
was	O
designed	O
to	O
be	O
used	O
for	O
amateur	O
radio	O
and	O
other	O
high	O
compression	O
voice	O
applications	O
.	O
</s>
<s>
Three	O
methods	O
are	O
used	O
for	O
error	O
control	O
:	O
binary	B-Error_Name
Golay	I-Error_Name
code	I-Error_Name
,	O
punctured	O
convolutional	B-Error_Name
code	I-Error_Name
and	O
bit	O
interleaving	O
.	O
</s>
<s>
This	O
ensures	O
that	O
there	O
are	O
as	O
many	O
symbol	O
transitions	O
in	O
the	O
baseband	B-Algorithm
as	O
possible	O
.	O
</s>
<s>
With	O
a	O
small	O
hardware	O
modification	O
,	O
TYT	O
MD-380	O
,	O
MD-390	O
and	O
MD-UV380	O
handheld	O
transceivers	O
can	O
be	O
flashed	O
with	O
a	O
custom	O
,	O
free	O
,	O
open	O
source	O
firmware	O
to	O
enable	O
M17	B-Device
support	O
.	O
</s>
<s>
Over	O
150	O
M17	B-Device
reflectors	O
exist	O
worldwide	O
as	O
of	O
December	O
2022	O
.	O
</s>
<s>
The	O
project	O
was	O
started	O
in	O
2019	O
by	O
Wojciech	O
Kaczmarski	O
in	O
Warsaw	B-Application
,	O
Poland	O
.	O
</s>
<s>
A	O
local	O
amateur	O
radio	O
club	O
he	O
was	O
a	O
member	O
of	O
,	O
SP5KAB	O
,	O
was	O
involved	O
in	O
digital	B-General_Concept
voice	O
communications	O
.	O
</s>
<s>
As	O
every	O
part	O
of	O
the	O
protocol	O
was	O
intended	O
to	O
be	O
open	O
source	O
,	O
Codec	B-Algorithm
2	I-Algorithm
released	O
under	O
the	O
GNU	O
GPL	O
2	O
license	O
,	O
has	O
been	O
chosen	O
as	O
the	O
speech	O
encoder	O
.	O
</s>
