Introduction to Microwave Introduction to Microwave Amateur RadioAmateur Radio

Steve Kavanagh, VE3SMASteve Kavanagh, VE3SMAApril 2008April 2008

What are Microwaves ?What are Microwaves ?

• Just radio waves with short wavelengths• Definition is imprecise, but usually means

frequencies above 1 GHz (1000 MHz)• Hams sometimes include 902 MHz band• Microwaves are fun !

Microwave Ham BandsMicrowave Ham Bands

• 902-928 MHz• 1240-1300 MHz • 2300-2450 MHz• 3300-3500 MHz• 5650-5925 MHz• 10.0-10.5 GHz• 24.0-24.25 GHz

• 47.0-47.2 GHz• 76.0-81.5 GHz *• 122.25-123.0 GHz *• 134-141 GHz *• 241-250 GHz

* = change in Table of Frequency Allocations – not yet in RIC-2

Types of ActivityTypes of Activity• DXing and Contests

– Mostly CW/SSB, some FM on 10/24 GHz, some digital modes– Portable activity is popular– Moonbounce

• FM Repeaters– Somewhat rare– 902 MHz & 1.2 GHz

• Amateur Television– Lots of bandwidth available– Activity on 902 MHz, 1.2, 2.3 & 10 GHz

• Satellites– 1.2, 2.4 & 24 GHz, so far

• High Speed Data

Propagation ModesPropagation Modes• Line of sight

– For gains that do not vary with frequency signal is much lower at shorter wavelengths - repeater/mobile operation works poorly above 2 GHz

– But for fixed antenna size signal is proportional to f2 - long distance point-to-point links with directional antennas work at virtually any frequency

• Need to avoid blockage by buildings, trees• Reflection paths• Tropospheric scattering, ducting• Rain (and snow) scatter• Moonbounce• No ionospheric propagation, aurora, meteor scatter (so

far !)

EquipmentEquipment

• Commercially built transceivers– Kenwood TS-2000X & Icom IC-910H (with optional

module) cover 1.2 GHz (multi-mode)– 1.2 GHz FM-only transceivers (and multi-band FM

handhelds covering 1.2 GHz) have been made but I am unaware of any current models

– ATV gear : PC Electronics makes TV transmitters & receivers for 902 MHz, 1.2 & 2.3 GHz

– Advanced Receiver Research TR-10GA & TR-24GA 10 & 24 GHz wideband FM radios (discontinued)

EquipmentEquipment

• Commercially available transverters– Convert a lower frequency rig (usually 28 or

144 MHz) to operate at a higher frequency– 902 MHz to 47 GHz transverters available

fully built or as kits from• Down East Microwave Inc. (Florida)• Kuhne Electronic (Germany)

EquipmentEquipment

EquipmentEquipment

• Homebrew & Surplus– Plenty of scope for the homebrewer who

wants a challenge • But often much easier than you might think !

– Some fairly easily converted commercial gear– Possibility of using 902 MHz, 2.4 GHz and 5.8

GHz wireless equipment – a good example is the “Wavecom Jr” 2.4 GHz TV transceiver.

AntennasAntennas• Mobile and other omnidirectional verticals

– Available from Comet (902 MHz), Diamond (multiband incl. 1.2 GHz)

• Yagi– OK for 902 MHz, 1.2 GHz, performance hard to maintain at

higher bands

AntennasAntennas• Helix

– Circularly polarized – Used for satellite work at 1.2 GHz

AntennasAntennas

• Loop Yagi– Good for 902

MHz to 3.5 GHz

– Available from Directive Systems in Maine

AntennasAntennas

• Horn– Useful from 3.3 GHz up– 10 & 24 GHz horns

available from Advanced Receiver Research (CT)

– Easy to make

AntennasAntennas• Dish

– Useful from 1.2 GHz up– Gain often > 30 dB

What Kind of DX is Possible ? What Kind of DX is Possible ? • Here are my results with modest gear (CW or SSB):

GHz Power, Antenna Best DX0.9 5 W, 7 el. Yagi VT, MA, NY, PA, OH 1.2 2 W, 27 el. Loop Yagi VT, MA, NY, PA, OH, MI

2.3 1 W, 55 el. Loop Yagi MA, NY, OH

3.4 1 W, 2 ft. dish MA, NY

5.7 5 mW, small horn 126 km (Scarborough-WNY)

10 250 mW, 2 ft. dish 403 km (Hamilton-Gatineau)

24 500 mW, 1 ft. dish 145 km (Burlington -WNY)

Canadian DX RecordsCanadian DX RecordsBand Type Stations km

3.4 Within CanadaCanada-USA

VE2JWH-W1AIM/VE2VE4MA-WA0BWE

424619

5.7 Within CanadaCanada-USA

VE2JWH-W1AIM/VE2VE4MA-WA0BWE

424619

10 Within CanadaCanada-USA

VE2JWH/VE2PIJ-W1AIM/VE2VE3KRP-KM0T

424791

24 Within CanadaCanada-USA

VE3TFU-VE3SMAVE4MA-W0ZQ

127174

47 Within CanadaCanada-USA

K2LDU/VE3-N2EZS/VE3K2LDT/VE3-WB2BYP

1130

World DX RecordsWorld DX RecordsGHz Stations km GHz Stations km

0.9 KH6HME-N6XQ 4064 47 AD6FP-W6QI 343

1.2 KH6HME-XE2/N6XQ 4143 76 W0EOM/AD6FP-KF6KVG

175

2.3 KH6HME-N6CA 3980 120* WA1ZMS/4-W4WWQ 30

3.4 KH6HME-N6CA 3980 122 WA1ZMS/4-W4WWQ 114

5.7 KH6HME-N6CA 3980 134 WA1ZMS/4-W4WWQ 114

10 4X/DJ4AM-I/DJ3KM 2079 144* WA1ZMS/4-W2SZ/4 80

24 WW2R/5-W5LUA 544 241 WA1ZMS/4-W2SZ/4 80

902 MHz (33 cm)902 MHz (33 cm)

• 902-928 MHz shared with ISM and unlicensed consumer equipment (mostly cordless phones) – QRM is a reality !

• SSB/CW stations in this area: – VE3BFM (nr. Alliston), VE3CRU (Whitby),

VE3OIL (Freelton), VE3NPB (Toronto), VE3TFU (Waterford), VE3SMA (Cambridge)

• Propagation similar to 70 cm (430 MHz)

1.2 GHz (23 cm)1.2 GHz (23 cm)

• 1240-1300 MHz shared with radar – I occasionally get radar QRM

• 1296 MHz SSB/CW stations in this area: – NP4B/VE3 (Hamilton), VE3BFM (nr. Alliston),

VE3TFU (Waterford), VE3OIL (Freelton), VE3NPB (Toronto), VE3SMA (Cambridge)

2.3 GHz (13 cm)2.3 GHz (13 cm)• 2.3-2.45 GHz shared with various services.

QRM from WLAN and cordless phones to satellite downlinks at 2401 MHz is common.– Can use WLAN (e.g. IEEE 802.11) equipment in

amateur service with higher power/bigger antennas than permitted without a licence.

• 2304 MHz SSB/CW stations in this area:– VE3CRU (Whitby), VE3OIL (Freelton), VE3NPB

(Toronto), VE3TFU (Waterford), VE3SMA (Cambridge)

• At least 70 identified stations recently active across Canada (all modes)

3.4 GHz (9 cm) & 5.7 GHz (6 cm)3.4 GHz (9 cm) & 5.7 GHz (6 cm)

• 3.4 GHz– Currently only VE3OIL (Freelton), VE3SMA

(Cambridge) and VE3TFU (Waterford) active in this area (CW & SSB at 3456 MHz).

• 5.7 GHz– Currently only VE3SMA (Cambridge) active in

this area (CW & SSB at 5760 MHz). VE3TFU will be on soon.

– VE3OIK has worked over 500 km (West Virginia) on this band

10 GHz (3 cm)10 GHz (3 cm)

• One of the most popular microwave bands• A few dozen southern Ontario hams have been

active over the past 20 years on both wideband FM and SSB/CW

• Currently active on 10.368 GHz SSB/CW in this area:– VE3CRU (Whitby), VE3NPB (Toronto), VE3FHM

(Georgetown), VE3TFU (Waterford), VE3SMA (Cambridge)

• Several others on WBFM

24 GHz24 GHz• Shared with various services but no QRM

problems observed• 24.192 GHz SSB/CW stations in this area:

– VE3SMA (Cambridge)– VE3TFU (Waterford)– VE3FHM (Georgetown) is under construction

• 24 GHz WBFM activity: – VE3SMA, VE3FHM, VE3VXO (Waterloo), VE3CRU

(Whitby), VE3EZP (London)• Water vapour absorption makes 24 GHz more

difficult.

47 GHz47 GHz

• Highest frequency for which commercial equipment is available

• Only activity in Ontario has been by visiting Rochester NY area hams

• VE4MA was the first ham anywhere to hear a signal on this band reflected from the moon (from RW3BP), and has now made a 2-way contact with him

76 GHz & Up76 GHz & Up

• Homebrew equipment only !• No activity yet in Canada, but VE4MA is

collecting parts• New allocations shared with radio

astronomy – do not expect any QRM !

LASER (470,000 GHz !)LASER (470,000 GHz !)

• Optical communication is not strictly amateur radio…but it is interesting to play with

• Because all frequencies above 300 GHz are allocated to amateurs in the USA it is considered a ham band in the USA and counts in ARRL VHF/UHF/Microwave contests

• Gear can be very simple• Transceiver kits available from Ramsey• Must be very careful with safety (potential for

eye damage, distracting drivers and pilots)

Simple Wideband FM GearSimple Wideband FM Gear

• Block Diagram

Lake Erie Propagation MagicLake Erie Propagation Magic

Lake Erie Propagation MagicLake Erie Propagation Magic

• Long Point (6 ft)-Morpeth (15 ft)...113 km– VE3OIK-VE3NPB/SMA ( 10 GHz SSB)– VE3OIK-VE3CRU (10 GHz WBFM)

• Long Point (6 ft)-Wheatley (12 ft)…172 km– Barely able to make contact on 2m CW (25 W each,

5-7 el beams at 10-18 ft)– VE3OIK-VE3NPB/SMA (10 GHz SSB, S-meters

pinned !)• Clarke Rd (60 ft)-Morpeth(15 ft)…91 km

– Much weaker signals

Lake Erie Propagation MagicLake Erie Propagation Magic• Some paths worked around Lake Erie

Awards and ContestsAwards and Contests• ARRL VHF/UHF Century Club (VUCC)

– Available for each VHF/UHF/Microwave band for working specified number of grid squares (2 longitude x 1 latitude)

• Contests involving microwaves:– ARRL VHF Sweepstakes (January)– SBMS 2 GHz & Up Contest (May)– 902 MHz & Up Sprints (May/October)– ARRL VHF QSO Parties (June/September)– ARRL UHF Contest (August)– ARRL 10 GHz & Up Contest (August/September)

Worldwide CommunityWorldwide Community

• Internet discussion groups:– WA1MBA Microwave Reflector

• See www.wa1mba.org

– Ontario VHF Association • www.ovhfa.com , http://home.cogeco.ca/~ovhfa/ • Email reflector:

http://groups.yahoo.com/group/OntVHFAssoc_reflector/

• Meetings– OVHFA Annual “Do”– Microwave Update Conference in USA

Worldwide CommunityWorldwide Community

• Microwave operators are a fairly small group, and always keen to have more people to work on the microwave bands

• I’ve found microwavers are usually helpful and generous with their time, expertise and even equipment

• Remember: help is always available to get you going !