1. General Radio Overview
SECTION 2 - Radio Technology Overview
Explain that this is just a brief overview of radio tech.

2. History of Wireless Wireless Has Come a Very Long Way
ESTeem has been wireless over 30 years
Patent on first wireless modem in 1984
Wireless Has Come a Very Long Way
Lower data rates 2,400 bps
Latest hardware 19,200 bps
First Generation for Serial Networks
Higher data rates in wideband channels
Spread Spectrum
Latest generations closing in on wired speeds
Open protocol standards
Wireless Ethernet (WLAN)

3. Primary Uses of Wireless
Moving Hardware
Maintenance Vehicles
Factory Floor Machines
Overhead Cranes
Public Safety
Mobile Applications

4. Primary Uses of Wireless
Difficult or Too Costly to Run Cable
Across waterways
Communication across roadways
Airfield lighting
“Inaccessible” Areas

5. Primary Uses of Wireless
City or County Coverage
Impracticable to Cable
Water Distribution
Wastewater Systems
Long Distance Communication

6. Spread Spectrum Advances Wireless
Originally a military communication technique used for anti-jamming
Allowed for civilian use by FCC in early 1990’s
Wide-band transmissions used for much higher data rates than narrow band
Used in many applications from cordless phones to wireless networks

7. Spread Spectrum Modulation
Data broken into small packets transmitted on moving frequencies
Very resilient to noise
Frequency Hopping
Combines data with spreading signal
Very efficient when signal strength greater than noise
Direct Sequence
Latest modulation technique
Efficiency (54 Mbps) and high noise immunity
Designed for non-line of sight urban operation
OFDM (Orthogonal Frequency Division Multiplex)

8. Line of Sight No Line Of Sight Repeater Remote Master
SECTION 2 - Radio Technology Overview
Repeater
No Line Of Sight
This is a classic example of an application that needs a repeater because there is no line of sight between the remote and the master. The repeater is set up so it can relay the message from the master to the remote site.
Master
Remote

9. Radio Characteristics
SECTION 2 - Radio Technology Overview
Transmission Speed
Turn-On time
Bandwidth
Transmitter Characteristics
Receiver Sensitivity
Receiver Squelch
Receiver Characteristics
The one thing inherent to all transmitters is the turn on time. This is the amount of time it takes for a transmitter to turn on to be able to transmit the out going message.
Bandwidth- is the width of the frequency that the radio is transmitting on.
transmission speed is dependant on the turn on time and the band width that the transmitter is transmitting
Receiver sensitivity and squelch are inversely proportional to each other. The higher the sensitivity the lower the squelch and vise versa

10. Bandwidth 20 MHz The Bandwidth Directly Controls Data Rate 10 MHz
SECTION 2 - Radio Technology Overview
The Bandwidth Directly Controls Data Rate
5, 10 ,20 MHz Bandwidth selections
20 MHz
10 MHz
VHF and UHF both have advantages and disadvantages, usually the advantages for one is the disadvantage for the other and vise versa.
11 Mbps
1 Mbps
5 MHz
54 Mbps

11. Spread Spectrum Most Spread Spectrum Radio Use Unlicensed Bands
Industrial Scientific & Medical (ISM)
900 MHz and 2.4 GHz
Unlicensed National Information Infrastructure (U-NII)
5.15 to GHz
Manufacturer Gets FCC Approval - Not User
Most Spread Spectrum Radio Use Unlicensed Bands
Frequency propagation has less loss than higher frequencies
Narrower bandwidth for fewer side by side channel operation
900 MHz Frequency Band
Greater bandwidths available for more frequency channels
Most common band for wireless Ethernet hardware
2.4 GHz Frequency Band
Very low noise floor and fewer users
Licensed for public safety/municipal applications
4.9 GHz Frequency Bands
Proprietary and a channels
5.8 GHz Frequency Band

12. Frequency Hopping
Breaks Information Signal (Data) Into Smaller, Moving Narrow Band Signals
Complexity Does Not Lie In The Spreading and De-Spreading Of the Data Signal but In Synchronization of Narrow Data Signal
Uses Spreading Signal to Change Frequency of Carrier (Hop) Across Band
Hopping in Patterns Greater Than 100 times/sec
Interference Handled by Moving Hopping Patterns

13. Frequency Hopping Diagram
Signal Strength
RFI
Frequency
Data
Data
Data Bit
Hopping
Data
Frequency
Hopping
Synthesizer
Frequency
Hopping
Synthesizer
Hop code
generator
Hop code
generator
Transmitter
Receiver

14. Direct Sequence
Combines Information Signal with Spreading Signal to Produce Wide-Band Transmission
Pieces of Each Bit Are Send Across Whole Band
Receiver Then Adds Back Up - Process Gain
If Some Pieces Are Lost They Don’t Add to the Overall Gain of Receiver, but Data is Not Lost
Any Interfering Signal Not In Original Spreading Code Signal is Then “Spread” Itself and Filtered Out in Receiver

15. Direct Sequence Diagram
Spread
RFI Signal
Signal Strength
RFI
Frequency
Data
Data
Spread
Data
Carrier
Filter
PN Sequence
generator
Spreading
Signal
Spreading
Signal
PN sequence
generator
Transmitter
Receiver

16. OFDM Latest Generation of Spread Spectrum
Available bandwidth divided into multiple data subcarriers
(52) 300kHz-Wide Subchannels
48 used for data and 4 used for error correction
All channels evenly spaced (Orthogonal)
All subcarriers transmit simultaneously for high spectral efficiency
Parallel data transmission paths
Resilient to RF interference
Low Mutipath distortion

17. OFDM Diagram Result After RFI RFI/Mutipath Data Data Data Stream
Evenly Spaced
Subcarriers
Result After RFI
Evenly Spaced
Subcarriers
Signal Strength
RFI/Mutipath
Frequency
Data
Data
Data
Stream
Simultaneously
Transmitted
Data
OFDM
Subcarrier
Generator
OFDM
Demodulator
Transmitter
Receiver

18. Antenna Fundamentals
SECTION 2 - Radio Technology Overview

19. Decibels (dB)
Used for all mathematical calculations in the radio world.
dB is a logarithmic number
dB =10 log (linear number)
A gain of 2 = 10 log (2) = 3 dB
A gain of 4 = 10 log (4) = 6 dB
When a number doubles it goes up 3 dB
When a number reduces by 1/2, it goes down -3 dB
To multiply linear numbers you add logarithms
To divide linear numbers you subtract logarithms

20. Antenna Gain
SECTION 2 - Radio Technology Overview
Antenna Gain measure in decibels (dB)
Doubles every 3 dB
Effective Radiated Power (ERP) = Tx Power + Antenna Gain - Feedline Losses
Received Signal = Rx Power + Antenna Gain - Feedline losses
As Antenna Gain increases Antenna Pattern becomes more directional
Antenna gain is a logarithmic equation, gain doubles for every 3db increase, but is cut in half for every 3db decrease.
High Gain antennas become more directional. This slide give an example of a High Gain UHF antenna.
Erp is the rf power plus or minus the gain or loss of the antenna. The loss that is incurred at the transmit site can quite possibly be made up at the receive site, through the same practice.

21. Radiation Patterns RF Energy Antenna Top View
Omni-Directional Antenna
Radiates RF energy in all directions from antenna
RF Energy
Antenna
Top View

22. RF Basics - Omni-Directional Antennas
Radiates RF energy in all directions from antenna
Usually used at the Master and Repeater Nodes
360 degrees
Omni-directional Antenna Vertical Polarized
Top View
Radiation Pattern Vertical Polarization
Side View
Radiation Pattern Vertical Polarization

23. RF Basics - Antenna Gain
As Antenna Gain increases the Antenna Pattern becomes more directional
Omni- Directional Antenna Shown Below
3 dB Points
360 degrees
Remains Unchanged
Vertical Beam Width (degrees)
Top View
Radiation Pattern Vertical Polarization
Side View
Radiation Pattern Vertical Polarization

24. Radiation Patterns RF Energy Antenna Top View
Directional Antenna
Compresses RF Energy in one direction
RF Energy
Antenna
Top View

25. RF Basics - Directional Antennas
Radiates RF energy in one direction
Usually used at Remote Nodes in a Point to Multi-point system or Point to Point Site
Side View Radiation Pattern Vertically Polarized
Vertical Beam Width (degrees)
Back Lobe
3 dB Points
Horizontal Beam Width (degrees)
Back Lobe
Top View Radiation Pattern Vertically Polarized
3 dB Points

26. RF Basics - Antenna Gain
SECTION 2 - Radio Technology Overview
As Antenna Gain increases the Antenna Pattern becomes more directional
Directional Antenna Shown Below
3 dB Points
3 dB Points
Horizontal Beam Width (degrees)
Vertical Beam Width (degrees)
Antenna gain is a logarithmic equation, gain doubles for every 3db increase, but is cut in half for every 3db decrease.
High Gain antennas become more directional. This slide give an example of a High Gain UHF antenna.
Erp is the rf power plus or minus the gain or loss of the antenna. The loss that is incurred at the transmit site can quite possibly be made up at the receive site, through the same practice.
Back Lobe
Back Lobe
Top View
Radiation Pattern
Vertically Polarized
Side View
Radiation Pattern Vertically Polarized

27. Directional Antenna Vertical Polarized
SECTION 2 - Radio Technology Overview
Antenna Polarization
Vertical Or Horizontal Polarization
Polarization is the radiating element referenced to earth
All nodes must be the same polarization
Cancellation of signal if mismatched
Vertical Polarization for Most Radio Applications
Mixture of Omni and Directional Antennas
No Horizontal Polarization of Omni-Directional
There are two types of polarization for antennas, they are vertical and horizontal. You must always place the antennas in the same polarization. If you do not theoretically they will never see each other. Thus they will effectively cancel each other out. Normally all antennas for SCADA applications the antennas are vertically polarized.
Directional Antenna Vertical Polarized
Omni-directional Antenna Vertical Polarized

28. RF Basics - Feedlines Feedline
Pipeline for RF Energy From Radio to/from Antenna
Different Cable Types Have Different Losses
The lower the loss the more expensive the cable
Losses Based Upon Length & Frequency
Expressed in dB/100 ft. by the manufacturer
The higher the frequency, the more attenuation in cables, connectors, etc.
All feedlines and connectors induce losses to RF energy

29. RF Basics - Feedline Attenuation Table
Feedline Attenuation (- dB/100 ft.)

30. Standing Wave Ratio (SWR)
Ratio of Maximum to Minimum Values in Standing Wave Pattern
Voltage (VSWR) or Current
Mismatch in Impedance (Antenna or Cable) Will Induce Standing Waves
Measurement of Forward and Reflected Power Most Field Expedient
Wattmeter ( i.e. Bird Model 43)

31. SWR Measurement To Antenna Transceiver Directional Watt Meter
Maximum = 10% Reflected Power
ESTeem commands to initialize transmitter
Radio ON command for serial
Advanced Menu 195E and 210
To Antenna
Transceiver
Directional
Watt Meter

32. Typical Outdoor Antenna Block Diagram
Interface Cable
Feedline
User’s Device
Lightning Arrestor
12 VDC Power Supply

33. Typical Indoor/Mobile Antenna Diagram
Interface Cable
Feedline
User’s Device
12 VDC Power Supply

34. Typical Model 195E Mounting
Model 195E Outdoor Fixed Base Hardware Diagram
External Antennas
Directional Antennas
Omni-Directional Antenna
Antenna Feedline
Weather Proof Boot
Direct Pole Mount
Pole Mounting Kit EST P/N AA195PM
Unit Shown With Rubber Duct Antennas
Weather Proof Front Cover
Weather Proof Boot
Direct Mount Antennas
Power Over Ethernet Cable
Ethernet Surge Protection EST P/N AA166
PoE Power Supply EST P/N AA175
Ethernet CAT-5e Cable 300 ft. maximum
Ethernet CAT 5e Cable EST P/N: AA09.2
To LAN Interface

35. Antenna Spacing Odd Multiples of 1/4 Wavelength Antenna Spacing
Spacing Odd multiple of 1/4 wave lengths
Measure from base of one antenna to tip of other
1/4 wave (in.) = 2952/freq. (MHz)
922 MHz = 3.20 inches
Odd Multiples
of 1/4 Wavelength