The
2.5-millimeter
or
122 GHz
band is a portion of the
EHF
(
microwave
) radio spectrum internationally allocated to
amateur radio
use between 122.250 GHz and 123.000 GHz.
[1]
The band is close to a
molecular resonance
of
oxygen
at 120 GHz, which causes significant
atmospheric
propagation losses
, similar to that found at 60 GHz.
Due to the lack of
commercial off the shelf
radios, amateurs who operate on the 2.5 mm band must design and construct their own equipment, and those who do, often attempt to set communication distance records for the band.
Allocation
[
edit
]
The
International Telecommunication Union
allocates 122.250 GHz and 123.000 GHz to amateur radio on a secondary basis. As secondary users, amateurs must protect the
fixed
,
mobile
and
inter-satellite
services from
harmful interference
, which share the band with amateurs. In addition, 122 GHz to 123 GHz is an
ISM band
, and all users must accept interference caused by ISM devices.
Amateur satellite
operations are not permitted, and the ITU's allocations are the same in all three
ITU Regions
.
[1]
List of notable frequencies
[
edit
]
- 122.250 to 122.251 GHz Narrow band modes
[2]
[3]
- 122.5 GHz
ISM band
center frequency
[1]
Distance records
[
edit
]
The current world distance record on the 2.5 mm band is 139 kilometres (86 mi) set by stations K6ML, KB6BA and N9JIM on February 17, 2020.
[4]
[5]
The previous world distance record on the 2.5 mm band was 132 kilometres (82 mi) set by
Austrian
stations OE5VRL and OE3WOG on October 19, 2013.
[6]
The previous
United States
distance record was 114 kilometres (71 mi) set by stations WA1ZMS and W4WWQ on January 18, 2005.
[5]
The longest distance achieved on 2.5 mm in the
United Kingdom
was 51.9 kilometres (32.2 mi) between stations G8CUB and G0FDZ in January 2023.
[6]
In
Australia
, the 2.5 mm distance record was 69.6 kilometres (43.2 mi) set by stations VK4FB and VK4CSD on July 18, 2019.
[7]
See also
[
edit
]
References
[
edit
]
- ^
a
b
c
"FCC Online Table of Frequency Allocations"
(PDF)
.
47 C.F.R
. Federal Communications Commission. May 7, 2019
. Retrieved
August 7,
2019
.
- ^
"VHF Managers Handbook"
(PDF)
. 7. International Amateur Radio Union Region 1. January 2015. p. 54
. Retrieved
October 27,
2015
.
- ^
"IARU Region 2 Band Plan"
(PDF)
. International Amateur Radio Union Region 2. October 14, 2016. p. 16.
- ^
"New World Distance Record Claimed on 122 GHZ"
.
- ^
a
b
"Distance Records"
(PDF)
.
Amateur Radio Relay League
. April 5, 2020
. Retrieved
September 6,
2020
.
- ^
a
b
Day, Peter; Quarmby, John (January 21, 2023).
"Microwave Distance Records"
. UK Microwave Group
. Retrieved
January 25,
2023
.
- ^
"Australian VHF - UHF Records"
(PDF)
.
Wireless Institute of Australia
. January 23, 2021.
Archived
(PDF)
from the original on August 1, 2021
. Retrieved
July 31,
2021
.
External links
[
edit
]
|
---|
Range
|
Band
|
ITU Region 1
|
ITU Region 2
|
ITU Region 3
|
LF
|
2200 m
|
135.7?137.8 kHz
|
MF
|
630 m
|
472?479 kHz
|
160 m
|
1.810?1.850 MHz
|
1.800?2.000 MHz
|
HF
|
80 / 75 m
|
3.500?3.800 MHz
|
3.500?4.000 MHz
|
3.500?3.900 MHz
|
60 m
|
5.3515?5.3665 MHz
|
40 m
|
7.000?7.200 MHz
|
7.000?7.300 MHz
|
7.000?7.200 MHz
|
30 m
[
w
]
|
10.100?10.150 MHz
|
20 m
|
14.000?14.350 MHz
|
17 m
[
w
]
|
18.068?18.168 MHz
|
15 m
|
21.000?21.450 MHz
|
12 m
[
w
]
|
24.890?24.990 MHz
|
10 m
|
28.000?29.700 MHz
|
VHF
|
6 m
|
50.000?52.000 MHz
(50.000?54.000 MHz)
[
y
]
|
50.000?54.000 MHz
|
4 m
[
x
]
|
70.000?70.500 MHz
|
?
|
2 m
|
144.000?146.000 MHz
|
144.000?148.000 MHz
|
1.25 m
|
?
|
220.000?225.000 MHz
|
?
|
UHF
|
70 cm
|
430.000?440.000 MHz
|
430.000?440.000 MHz
(420.000?450.000 MHz)
[
y
]
|
33 cm
|
?
|
902.000?928.000 MHz
|
?
|
23 cm
|
1.240?1.300 GHz
|
13 cm
|
2.300?2.450 GHz
|
SHF
|
9 cm
|
3.400?3.475 GHz
[
y
]
|
3.300?3.500 GHz
|
5 cm
|
5.650?5.850 GHz
|
5.650?5.925 GHz
|
5.650?5.850 GHz
|
3 cm
|
10.000?10.500 GHz
|
1.2 cm
|
24.000?24.250 GHz
|
EHF
|
6 mm
|
47.000?47.200 GHz
|
4 mm
[
y
]
|
75.500 GHz
[
x
]
? 81.500 GHz
|
76.000?81.500 GHz
|
2.5 mm
|
122.250?123.000 GHz
|
2 mm
|
134.000?141.000 GHz
|
1 mm
|
241.000?250.000 GHz
|
THF
|
Sub-mm
|
Some administrations have authorized spectrum for amateur use in this region;
others have declined to regulate frequencies above 300 GHz.
|
[
v
] All allocations are subject to variation by country. For simplicity, only common allocations found internationally are listed. See a band's article for specifics.
[
w
] HF allocation created at the 1979
World Administrative Radio Conference
. These are commonly called the "
WARC bands
".
[
x
] This is not mentioned in the
ITU
's
Table of Frequency Allocations
, but many individual administrations have commonly adopted this allocation under
"Article 4.4"
.
[
y
] This includes a currently active
footnote allocation
mentioned in the ITU's
Table of Frequency Allocations
. These allocations may only apply to a group of countries.
|
See also:
Radio spectrum
,
Electromagnetic spectrum
|
|