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Rocky Mountain Ham University
Microwave Data Transmission
John Maxwell, W0VG [email protected]
Doug Sharp, K2AD
What you’re going to learn o Amateur Data/Voice/Control
o Legal Requirements/Restrictions
o Path Calculation Software
o ERP Calculation/Reliability
o Equipment available to do this
o Practical deployment scenarios
o Examples
Amateur Data Transmission
Voice Transport • No more dicey analog links! • Audio level reliability • Excellent high quality audio High Bandwidth • Very high bandwidth capability • 25-150mbps throughput Simple Monitoring • Due to IP structure monitoring of
services, voltages, throughput and reliability are easy to watch
A great start with DMR/TRBO. It’s time to take the next step!
Why do I need it? What am I going use it for?
Voice Transport/Linking/IP Phones • Having an IP based link network in place opens up many new
avenues for amateur radio.
• All Star Linking o This method uses Voice Over IP to transport repeater data from site to site or around the
world! From simple to difficult to implement depending on your needs. Documentation is horrible. Most of our implementation was trial and error.
• D-STAR linking o Icom proprietary networking in original form, there is an “open” standard called FreeStar
that is gaining ground. Not trivial to set up and maintain. Requires PC on-site to work.
• DMR systems o Commercial digital mobile radio implementation in high use on the amateur radio bands.
Simple implementation, easy deployment.
• IP Telephones • Command and Control • Telemetry • IP Cameras
What can I use it for?
Very high bandwidth • Typical FSK data transmission methods for Amateur Radio are
measured by “bits per second” o HF PSK about 50 words per minute o RTTY about 150-300baud o VHF Packet 1200baud over the air (300ish baud actual) o UHF/9600 baud packet over the air (1200ish baud actual) o D-STAR Data 1200 baud o D-STAR 1200Mhz data 128kbps o MotoTRBO data 4800baud
• Microwave data network in worst case scenario o 10mbps data throughput
• Microwave data network in Best case scenario
o 100mbps data throughput bi-directional
Systems Monitoring
Use tools available for free to watch your network!
Free Tools to watch your network • Observium – Temp, Voltage, Throughput, Logging • Smokeping – Packet Loss and Alerting • Cacti – Throughput via SNMP • Network Weathermap plug-in for Cacti
Systems Monitoring The two-way, IP network opens up many avenues for monitoring of devices and conditions in the real world. Systems are easily accessible via known network protocols like SNMP! You can run unmonitored, but you really should have visibility!
Use tools available for free to watch your network!
Systems Monitoring
Use tools available for free to watch your network!
Smokeping (showing packet loss and none)
Systems Monitoring
Use tools available for free to watch your network!
Cacti
Systems Monitoring
Use tools available for free to watch your network!
Network Weathermap
Legal Restrictions on Data Transmission • You must put a legal callsign in the SSID field to be legal
• ERP Limit (NONE!) o The FCC in 2011 removed the requirement for automatic power control on
Spread Spectrum signals, and limited PEP power to 10W from 100W. This is not a bad thing!
• No Encryption Allowed - INCLUDING WEP/WPA/WPA2
o Amateurs have never been able to transmit encrypted signals. Use of WEP/WPA or WPA2 signals would be against the FCC Rules. Do not use them in Amateur Service.
• Use a published format!
o Some manufacturers have created “proprietary” extensions to 802.11 and unless published could be construed as obfuscation.
o When in doubt, stick to 802.11
Keep it legal.
Path Calculation Software • Finding out whether a path works is a challenge. Lots of research
and engineering used to be needed. In most cases, it’s as simple as a click!
Radio Mobile Online hPp://www.cplus.org/rmw/rmonline.html
ERP/Path Calc Software • Doing path calculation is not a simple thing to do without some tools.
Then it becomes trivial. Radiomobile Online will do much of the heavy lifting for you if you build your links with REAL numbers.
• I use a simple Excel spreadsheet that I wrote to figure it out, fast.
ERP Calc available on RMHAM.ORG under RMHAM-‐‑U, Course Syllabus
ERP CALC
Path Length Freq in
TX Power TX Loss Ant Gain ERP in Miles GHz Path Loss Ant Gain RX Loss RSL RX Threshhold Fade Margin
33 0.5 34 66.5 59 5.925 147.47 34 0.5 -‐47.47 -‐72 -‐24.53
Reading Equipment Cut Sheets • In order to calculate the path information, you have to know the
radio specifications! Find a cut sheet for your gear and enter the numbers.
Cut sheets available from the equipment manufacturer.
ERP CALC For Mikro3k Netmetal 5 RB921UAGS-‐5SHPacD-‐NM, TX/RX at MCS9
Path Length Freq in TX Power TX Loss Ant Gain ERP in Miles GHz Path Loss Ant Gain RX Loss RSL RX Threshhold Fade Margin
25 0.5 34 58.5 59 5.925 147.47 34 0.5 -‐55.47 -‐72 -‐16.53
Shoot for 15-20db+/
More = Better!
Commerical Off-‐‑The-‐‑Shelf Gear • Ubiquiti, Engenius, Mikrotik, are just a few of the manufacturers that
have gear that are capable of going into the “ham” bands.
• If you’re not in a RF active/Noisy area, you can use ISM bands
Many options available.
Show the gear • Small - Ubiquiti Nano or Mikrotik SXT • Medium – Ubi Powerbridge M/Mikrotik QRT or
DynaDish 5 • Large – Ubi Rocket M5 or Mikrotik Netmetal 5 & Dish
• Being a good RF neighbor o Use directional antennas whenever possible o It’s OK to use OMNIs when necessary.
Know your equipment frequencies! • Ubiquiti equipment is very user friendly and simple to configure.
International versions of the equipment will generally cover the appropriate ham bands. Some vendors don’t carry International!
• Restrictions that the FCC has just enacted on manufacturers are making it more difficult to use radios out-of band!
• RMHAM’s choice for gear is Mikrotik and UBTik radios. Much of the Mikrotik’s current product is capable of being operated in the ham bands.
• Small and light Mikrotik DynaDish 5 is easily capable of 20 miles. Cost
effective.
• Choose your equipment based on your desired frequency
• 3.3-3.5GHz, 5.65-5.925GHz are available
• Example: Weak signal operates at 3456.1 MHz and 5760.1 MHz, so don’t run an omni system using 3450-3460MHz for your backbone!
• Also avoid the Terminal Doppler Weather Radar (TDWR) systems … it’s both illegal and they are a massive interference source for your microwave system receiver.
RMHAM Uses hPp://balticnetworks.com for our equipment
Let’s look at the
Ubiquiti
NanoStation M5
Datasheet
NanoStation M5
Quite a versatile
liPle unit …
But short range
Three models and
multiple frequency
bands …
So make sure you
use the correct
datasheet!
And some useful
tools
Finally a
specification sheet!
Now this is a useful
page!
Practical Deployment Scenarios
Let’s Configure the M5 units
Ubiquiti Rocket M5 -‐‑ Main Screen
Ubiquity Rocket M5 -‐‑ Wireless Screen
Ubiquity Rocket M5 -‐‑ Main Screen
Ubiquity Rocket M5 -‐‑ Network Screen
Ubiquity Rocket M5 – Advanced Screen
Ubiquity Rocket M5 -‐‑ Services Screen
Ubiquity Rocket M5 -‐‑ System Screen
www.rmham.org
