The Last Mile - PowerPoint PPT Presentation

About This Presentation
Title:

The Last Mile

Description:

The Last Mile Bridging the Gap By KS4JU What is the Last Mile ? The last mile is the path across an area where conventional communications have been disrupted ... – PowerPoint PPT presentation

Number of Views:689
Avg rating:3.0/5.0
Slides: 61
Provided by: MikeEl3
Category:
Tags: antenna | basics | last | mile

less

Transcript and Presenter's Notes

Title: The Last Mile


1
The Last Mile
  • Bridging the Gap
  • By
  • KS4JU

2
What is the Last Mile ?
  • The last mile is the path across an area where
    conventional communications have been disrupted
    or overloaded by an incident.

3
Why Digital Radio?
  • More Robust
  • Can work better in noisy RF environments
  • Built in filtering or data redundancy improve
    communications
  • Can be more efficient with less power and smaller
    antennas.
  • Greater Connectivity
  • Some modes can be linked over the Internet to
    reach more potential users
  • Communicate More Efficiently
  • Greater bandwidth capability for more information
  • Potential for sending documents, photos and
    other attachments.
  • Provides more accurate communications

4
Digital Radio Tools
  • PSK31
  • HF
  • APRS
  • VHF
  • HF
  • Internet
  • Echolink
  • VHF
  • Internet
  • Winlink
  • HF
  • VHF
  • Internet

5
Radio
  • HF or VHF Radio
  • Most radios will work
  • Computer control interface can be useful, but not
    necessary
  • Compact low power capable radios can be used for
    field work or ran more efficiently on emergency
    power supplies.

6
Computer
  • Most digital amateur radio software have very
    modest computer hardware requirements
  • Laptops are more useful in emergency operations.
  • Portable
  • Self contained power supply
  • Low power requirements for emergency power.
  • Be sure to look into battery efficient laptops
    for emergency use

7
Computer / Radio Interface
  • Interface needs to be made between the computer
    sound card and radio for PSK31, APRS (AGW packet
    engine), Winlink (AGW Packet Engine), and
    Echolink server.
  • Sound card out to Radio mike input
  • Sound card input to Radio speaker / headphone
    output
  • Computer serial or usb port to Radio PTT
  • Interfaces can be made or purchased
  • Vendors
  • Rigblaster - West Mountain Radio
    www.westmountainradio.com
  • MFJ www.mfjenterprises.com
  • Saratoga Amateur Radio Parts - www.saratogaham.com
    /ezpsk/
  • Note
  • APRS can be used with a standalone 9600 baud
    hardware TNC
  • Winlink HF requires a dedicated Pactor 3 modem.

8
Software
  • Usually low cost or free

9
PSK-31
  • Advantages
  • Very easy to deploy in an emergency
  • Modest equipment requirements
  • Laptop, Radio Interface, HF Transceiver, Antenna,
    and Power Supply
  • This can include a low power HF transceiver,
    portable power supply, and portable antenna.
  • Very Robust
  • Can provide long range communications using HF in
    noisy conditions.
  • Can provide keyboard contact over long distances
    as well as short bulletins.
  • Does not rely on other technologies to work.
  • Possibly the best (only choice) during a
    widespread communications outage.
  • Disadvantages
  • Transfer of information slow (low bandwidth)
  • Can be affected by HF conditions (Propagation)
  • Not as useful for local or short-range
    communications
  • No redundancy
  • Limited connectivity

Official PSk-31 Website http//aintel.bi.ehu.es/ps
k31.html
10
PSK-31 Frequencies
  • PSK-31 activity is concentrated around the
    following frequencies
  • 1.83815 MHz
  • 3.580
  • 7.035 MHz
  • 14.07 MHz (Most Popular)
  • 18.100 MHz
  • 21.070 MHz
  • 24.920 MHz
  • 28.120 MHz
  • 50.290 MHz

11
PSK-31 Basics
  • PSK-31 uses Binary Phase Shift Keying (BPSK)
  • The keying rate is 31.25 bits/sec
  • The effective speed for plain English text is
    approximately 50 words/minute

12
PSK-63
  • PSK-63 offers
  • 100 wpm character transmission speed for contest
    exchanges and  macro transmission versus RTTY at
    60 wpm
  • Only 1/5 the bandwidth of RTTY - capable of
    displaying 25 signals simultaneously on a
    waterfall or spectrum display
  • Fast, easy, point-and-click tuning using the
    mouse or keyboard arrowkey tuning
  • Capable of color thumbnail portrait transmission
    in less than 2 minutes
  • Faster sync recovery than RTTY, resulting in
    fewer errors
  • Requires much less power than RTTY for the same
    communications performance
  • Identical to PSK31 except for a wider bandwidth
    of 63 Hz
  • Improved polar path performance compared to PSK31
  • Works with any soundcard-equipped Windows
    computer and SSB transceiver
  • Initial testing on 20 meters between 14072.5 and
    14080.0 KHz
  • Lots of software for PSK63 is available now!

PSK 63 Resource Page www.qsl.net/kh6ty/psk63
13
PSK-31 Performance
  • Real World Performance
  • The power in a PSK-31 signal is concentrated in a
    31 Hz bandwidth, versus 250 Hz for RTTY and 3300
    Hz for SSB the PSK-31 signal is brighter (3.2
    W/Hz vs 30 mW/Hz for SSB)
  • If a 100 W PEP ( 11 15 W rms) signal provides
    a 20 dB S/N ratio at the receiver using SSB, the
    same S/N ratio is achieved with 8W using RTTY and
    only 1W using PSK-31!
  • Transcontinental QSOs using PSK-31 are possible
    using less than 50 W under any conditions and
    when conditions are good, QRP (lt 5W) PSK-31
    contacts are possible to any point on the planet.
  • Unlike AMTOR, PACTOR, and packet, PSK-31 supports
    net operation (no handshaking required between
    stations)

14
Bandwidth Utilization
  • Waterfall display on the left shows several RTTY
    signals
  • Waterfall display on the right shows several
    PSK-31 signals
  • For the nearly the same character rate ( 50 wpm)
    PSK uses 1/5 the bandwidth
  • A 3 kHz SSB channel can support 10 or more PSK
    QSOs

15
Tuning in a PSK-31 signal
  • Turn on the equipment
  • Run the PSK software
  • Select the waterfall display mode
  • Use the mouse to place the cursor on a signal
  • Adjust the squelch until text appears in receive
    window

Receive Window
16
Recommended Software for PSK
  • Ham Radio Deluxe
  • hrd.ham-radio.ch

17
APRS
  • Advantages
  • Modest Equipment Requirements VHF Radio,
    Computer, Interface or TNC, and Software
  • Can be used for
  • Map based asset management.
  • Tracking people or objects.
  • Weather reporting
  • Short messages
  • Large radio based network with internet
    connectivity
  • Can be deployed quickly and portable / mobile
  • Still heavily used
  • Disadvantages
  • Need to be in range of an APRS node to
    participate in the network or internet
    connectivity.
  • Not a strong VHF network in the Athens Area

APRS Wiki info.aprs.net/wikka.php?wakkaAPRS
18
APRS Frequencies
  • USA National Frequency 144.39 MHz
  • Low Powered Trackers 144.99 MHz
  • Satellites
  • ISS 145.990- MHz UP 145.800 MHz- Down 1200
    Baud AFSK
  • PCSAT-2 145.825- MHz UP 435.275 MHz- Down
    1200 Baud AFSK
  • PCSAT-1 145.825MHz UP 145.825 MHz Down - 1200
    Baud AFSK
  • AO-51 145.860- MHz UP 435.150 MHz Down 9600
    Baud FSK
  • Web Access
  • www.findu.com
  • Open APRS
  • Based on Google Maps www.openaprs.net/

19
RecommendedAPRS Software
  • AGW Packet Engine Pro
  • Replaces the need for a hardware TNC
  • Requires PC with Soundcard
  • 50 License
  • Supports many TNC based Applications
  • AGW Tracker APRS Software
  • Very sophisticated mapping features using online
    maps
  • Very good weather displays
  • Supports standalone Kenwood APRS radios
  • Only program that is currently being updated

20
Athens APRS Activity 8/30/06
21
Coverage
22
Messages
23
Weather Data
24
Tracking
25
Satellite
26
Hurricane Tracking
27
Emergency Planning
28
Echo LinkVOIP / Protocol
  • Advantages
  • Can only require a computer, microphone, and
    Internet Connection
  • Allows monitoring or communicating on VHF
    repeaters world wide
  • Can be used to access distant repeaters for
    message handling during emergencies
  • Can be used to extend the range of local
    repeaters
  • Conferencing supported
  • Mobile transmitters can access remote repeaters
    via DTMF codes
  • Transmit automated messages with 3rd party
    software
  • Easy to use
  • Must validate Amateur Radio license before using
  • Disadvantages
  • Requires a live internet connection or a VHF
    vocie link to a radio connected to an Echo link
    server with a working internet connection.

Echolink www.echolink.org
29
PC as a Base Station
Home PC
VHF Repeater (Anywhere in the World)
Internet
VHF Radio
Base Microphone
Echolink Sysop Server
30
Mobile Link
Echolink / PC
VHF Repeater (Anywhere in the World)
Internet
VHF Radio
Mobile
Echolink Sysop Server
31
Echolink Overview
32
Advanced Controllers
  • Advanced controllers allow
  • Shutting down or rebooting the computer remotely
  • Remote access to controller functions from a
    mobile radio
  • Time out timer to unlatch PTT in case program
    hangs up
  • More suited for Echolink Sysop mode.
  • Priced from 75 to 135 (will work with other
    modes discussed here)
  • From VA3TO www.ilinkca.com and iLinkboards
    www.ilinkboards.com

33
SoftwareMain Page
34
Echolink Status09/31/06
35
Echolink Connect Screen
36
www.voipwx.net
37
WXTALKNode 7203
38
Winlink
  • Advantages
  • Modest equipment requirements for VHF access
    VHF radio, computer, interface, MS Outlook
    Express, AGW Packet Engine, and Paclink Post
    Office
  • Based on SMTP E-mail
  • Most emergency agencies rely on email for
    information transfer
  • Can send attachments for photos and documents
  • Redundant network utilizing radio and internet
    connectivity
  • Was proven very effective for Last Mile
    Communications in the hurricane Katrina
    aftermath
  • Disadvantages
  • HF links can be costly because of the requirement
    for a proprietary Pactor 3 modem
  • VHF access is fairly limited in Athens area
    (however, it would be easy to set up a local
    Telpac station)
  • Can be more complex to set up

Winlink - www.winlink.org
39
Why Winlink
  • Our traditional methods fail for complex message
    handling in todays agency environment!
  • Need for delivering written procedures, lists,
    graphics, images, and Pre-defined, formatted,
    documents to multiple recipients!
  • Multiple recipient e-mail with binary attachments
    is the de facto standard to carry written
    information.
  • Hand-written message forms are seldom used, and
    are not transparent to normal operations!
  • For complex messages, voice, Morse code,
    Radiograms, and traditional Packet radio wont
    do
  • way too slow, translation required, inflexible,
    prone to error, no permanent record, not
    self-originating, not point-to-multipoint.
  • doesnt go end-to-end from user-to-user on their
    own computers in their own offices no
    attachments and no automatic distribution..

40
E-MAIL VIA HAM RADIO using Winlink 2000
This is a Winlink 2000 PACLINK station.
A typical ham radio last mile e-mail station is
composed of simple components, even for an Agency
with multiple computers.
A VHF or UHF Radio and a Good Antenna
A D-Star or Packet Radio Modem (TNC.)
  • Laptop for a Portable Station. Desktop for an
    agency.
  • Paclink AGW Paclink Postoffice mini e-mail
    server software with
  • AGW Packet Engine Pro and
  • Outlook Express or Outlook
  • Win2000 or WinXP

Laptop Computer
41
E-MAIL VIA HAM RADIO
To send or receive e-mail, this station makes a
connection with a Winlink radio node or PMBO.
Computer
42
E-MAIL VIA HAM RADIO
For the last mile, use VHF radios and the
Packet mode as a pathway to carry e-mail.
Computer
43
E-MAIL VIA HAM RADIO
For longer distances or in difficult terrain,
most PMBOs are outfitted with multi-band HF
radios and the Pactor II III modes to serve
stations with no other e-mail outlet.
Airmail client Program
Users on HF have a special e-mail program called
Airmail.
44
E-MAIL VIA HAM RADIO
The PMBO is connected to the internet at all
times.
Computer
The Internet
45
E-MAIL VIA HAM RADIO
PMBOs may have remote gateways called TELPAC
stations. They are connected to the PMBO via any
TCP/IP link and duplicate its VHF radio port in
another location.
TELPAC stations may communicate to the PMBO via
any TCP/IP link, including ICOMs D-Star or
WiFi 802-11b.
Computer
802-11b
The Internet
46
E-MAIL VIA HAM RADIO
Other computers, or CMBOs, organize and manage
the network traffic.
CMBOs are transparent to users. They are
redundant, and you never know they are there.
Computer
The Internet
CMBO
CMBO
CMBO
47
E-MAIL VIA HAM RADIO
You can send radio e-mail directly to internet
e-mail users.
Computer
The Internet
48
E-MAIL VIA HAM RADIO
And you can send radio e-mail to other Paclink or
Airmail stations like yours.
The Internet
49
E-MAIL VIA HAM RADIO
Adding a LAN on the PACLINK computer permits
individuals to send and receive radio e-mail.
PACLINK is now an e-mail server.
PACLINK may be placed in the DMZ zone in front
of the firewall.
The Internet
Served Agency LAN
50
E-MAIL VIA HAM RADIO
The PMBO forwards radio e-mail between its radio
users, even if its internet connection is gone.
Computer
The Internet
51
E-MAIL VIA HAM RADIO
If the local PMBO has an outage, you can make a
connection with a local TELPAC station which will
automatically shift to a distant host PMBO with
connectivity. Or
The Internet
52
E-MAIL VIA HAM RADIO
Or you can traverse the packet network using
nodes to get to a connected TELPAC or PMBO. Or
The Internet
53
E-MAIL VIA HAM RADIO
Or you can use an HF station to get to a distant
connected PMBO using Airmail.
The Internet
54
E-MAIL VIA HAM RADIO
Besides radio channels, PACLINK stations also may
have telnet channels to the internet. This is
handy for fixed stations because it is fast.
PACLINK stations automatically switch between
preset radio destinations and telnet channels to
find a connection to a PMBO.
My E-mail server is down
The Internet
55
PMBO Locations
56
US Telpac Nodes
57
Nearby Telpac Stations Overview
58
Nearby Telpac Stations Detail
59
Devise a Plan!
  • Insure that there is no duplication of efforts in
    your last mile coverage area.
  • Set up an strategy for implementation with your
    local ARRL ARES or RACES organization. Set up a
    time-line for each task.
  • Coordinate efforts with the Winlink 2000
    Development Team, ECs,SECs,DECs/SM, etc.
  • Ask other ARES communities for assistance.
  • Set up personnel responsibilities with
    Time-lines!
  • Handle the finances. How much will it actually
    cost? Who should pay?
  • Involve and commit the end-user. They are the
    ones to benefit!
  • Implement the plan in stages.
  • Test it, and Test it again.
  • Provide a presentation and demo for your served
    agencies.
  • Continue to promote your capabilities.

60
Questions?
Write a Comment
User Comments (0)
About PowerShow.com