Broadband Wireless
Communications at E-Band
Capabilities and Spectrum Management Issues
Presented by:
John A. Lovberg, Ph.D.
Chief Technology Officer
Loea Communications Corporation
70/80 GHz Wireless Communications
Ideal for Medium-haul Broadband
Rapidly Deployable
Set-up times from hours to days depending
upon local facilities and terrain, providing
fiber-speed digital data transfer with no
trenching required
Single-hop link distance to 10 miles allows
fast, easy connection to remote locations
 Flexible
 Interfaces to Gigabit-Ethernet (1.25 Gbps), or to Sonnet optical-carrier
OC-12, OC-24, or OC-48 (622 Mbps, 1.244 Gbps, or 2.488 Gbps)
 Fiber-optic input/output acts as a “virtual fiber splice” for 1310 nm (OC)
or 852 nm (Gig-E) input/output wavelength
 Re-configurable
 Link hardware can be moved quickly and easily for optimum utility
 Reliable
 Operates through clouds and fog, where FSO technology fails
L1011-V/4-2
Loea Communications Corp.
Available MMW Spectrum for
Broadband Communications
 71-76 GHz – fixed point-to-point service allocation
 No FCC service rules currently exist
 Government co-primary, but minimal use to date
 81-86 GHz – fixed point-to-point service allocation
 No FCC service rules currently exist
 Government co-primary, limited current use in military
communications
 92-95 GHz – FCC OET initiative
 Championed by Dr. Michael Marcus since July 2000, to unleash
considerable commercial utility of MMW spectrum
 Government co-primary, band currently used for military radar and
communications
 FCC NPRM currently being drafted for all three bands
L1011-V/4-3
Loea Communications Corp.
Higher Frequencies, Narrower Beams
Alter Band Management Paradigms
 Motivation
for Band Management is to Allow Equitable Sharing of
Airwaves as a Limited Resource
 As this resource becomes unlimited (e.g. for FSO “pencil beams” at 350
THz), band regulation can be relaxed
Below 5 GHz:
 Omni-directional (broadcast) transmission  high
spectral scarcity, resolvable through spectrum
parceling only; Gives rise to band auctioning and
geographical-area licensing
5 GHz – 40 GHz:
 Directional (narrowcast) transmission  less spectral
scarcity, resolvable through combined spectrum and
spatial parceling; Motivates band segmentation
Above 40 GHz:
 Pencil-beam transmission  no spectral scarcity,
resolvable through spatial parceling alone; Eliminates
motivation for band auctioning and geographical-area
licensing; Eliminates motivation for band segmentation
L1011-V/4-4
Loea Communications Corp.
Narrow Antenna Beams Above 70 GHz
Allow Unlimited Reuse of Spectrum
A
D
A
C
B
C
D
B
No interference from
crossed “pipes”
A
No interference with one
common terminus
A
C
C
B
D
Interference with both
ends common (R<50)
L1011-V/4-5
B
RELAY
D
Midpoint relay redirects one
link along alternate path
Loea Communications Corp.
Atmospheric Attenuation
Favors 70 GHz in Weather
ATTENUATION, dB/km
100
10
1.01.0
0.10
RH=0%
0.01
0
50
100
71
94
150
200
250
300
350
FREQUENCY, GHz
 Atmospheric attenuation in dry air (10% RH at 15°C) has local
minimum at 94 GHz
 In humid air, minimum moves to 71 GHz, better for reliable
“medium haul” operation in weather
L1011-V/4-6
Loea Communications Corp.
1.25 Gbps, 72 GHz Transceiver
Power Budget

1.25 Gbps, 72 GHz Link Budget:
Pr  Pt

Gt Gr λ 2 Latm LH 2O L fog Lrain
4π 
2
R
2
 Pnoise (S/N )( NF)
72 GHz Transceiver Characteristics:
Pnoise = –82 dBm (receiver noise floor, 1.6 GHz noise bandwidth)
S/N = 13 dB
(signal-to-noise ratio for 10-10 BER, using OOK)
NF = 7 dB
(receiver noise figure)
Gt = 56 dB
(gain of 4-foot dish TX antenna)
Gr = 56 dB
(gain of 4-foot dish RX antenna)
2 = –48 dBsqm (72 GHz wavelength)
L1011-V/4-7

Latm LH 20 L fog Lrain
R2
(4)-2 = –22 dB
(constant factors)
Pt = +29 dBm
(TX power at proposed maximum EIRP = +55 dBW)
 133 dB m - 2
Loea Communications Corp.
“Last-mile” Link Availability
Dictated by Local Rain Rates

1.25 Gbps, 72 GHz “Last Mile” Rain Fade Analysis:
Latm LH 2O L fog Lrain
R2
0.78
 133 dB m - 2 , Lrain  0.87 F dB/km, at 72 GHz
R-2 = –64.1 dB m-2 (1.61 km “last mile” range)
Latm = –0.3 dB
(atmospheric loss = 0.21 dB/km at 72 GHz),
LH2O = –0.9 dB
(water vapor loss = 0.56 dB/km at 72 GHz, for 100% RH, air temp 10C),
Lfog = –5.1 dB
(fog loss = 3.2 dB/km at 72 GHz, for 1 gm/m H2O, air at 10C, 50 m vis),
leaving a total rain fade margin of:
Lrain = –62.6 dB
(rain loss to 38.9 dB/km;  F = 131 mm/hr over entire link path,
 > 99.999% availability all US rain zones except extreme Southeast,
> 99.996% in Southeast zone
L1011-V/4-8
Loea Communications Corp.
Loea Link at 99.999% Availability:
Range By Rainfall Region
1.8
miles
1.5
miles
1.4
miles
1.7
miles
1.2
miles
1.1
miles
0.9
miles
L1011-V/4-9
Loea Communications Corp.
Loea Link at 99.99% Availability:
Range By Rainfall Region
3.7
miles
3.0
miles
2.5
miles
3.4
miles
2.1
miles
1.7
miles
1.3
miles
L1011-V/4-10
Loea Communications Corp.
Loea Link at 99.9% Availability:
Range By Rainfall Region
8.1
miles
6.7
miles
5.6
miles
8.1
miles
4.5
miles
3.5
miles
2.6
miles
L1011-V/4-11
Loea Communications Corp.
Current 70 / 80 GHz Development
and Regulatory Status
 Technology demonstrated
 8-mile link operating at 1.25 Gbps in Maui,
using 5 mW Tx power, BER < 10-12
 Loea facility (Kihei) linked to Mt. Haleakala
radio tower through permanent cloudbank
Renaissance
 FCC petition RM-10288 filed by Loea
in September 2001, recommending:
 Fixed point-to-point licensing based upon
existing part 101 provisions
 Third-party frequency/path coordination
 Proscription of auctions and area-licenses
C.O.
MRTC
Trex
Coating
Facility
1.25 Gbps
Fiber DS3
 Petition subsequently put out for comment
 Responses unanimously supportive, from WCA, several WCA-member companies,
telecom hardware companies, telecom service companies, satellite industry
 Briefings to NTIA and IRAC have also yielded positive responses
 FCC Notice of Proposed Rule-Making (NPRM) now in process
L1011-V/4-12
Loea Communications Corp.
Petition for New Bands Uses
Existing Regulatory Framework
 New Regulations Based upon Existing Rules for Fixed Point-to-Point
Microwave Services, Listed under CFR Section 47, Part 101
 Add 71-76 GHz and 81-86 GHz Bands, with:
Authorized Bandwidth - Part 101.109(c) – Max bandwidth: 5,000 MHz
 No segmentation of either frequency band
Transmitter Power, Part 101.113(a) – Maximum EIRP: +55 dBW
 Commensurate with limits on other bands > 19.7 GHz; 800 mW Tx with 4-ft dish
Antenna Gain/Beamwidth, Part 101.115(c) – Min Gain 50 dBi, Max
HPBW 0.6
 Gain 12 dB higher than other bands >19.7 GHz, enables spatial-parceling
paradigm
 Modulation Spectral Efficiency - Part 101.141 – No limits
 Commensurate with other bands above 19.7 GHz
 Airwave resources shared on geographical basis, not through spectrum parceling
L1011-V/4-13
Loea Communications Corp.
Managed Path Coordination
Monitors Geographical Deployment
 Link registration consolidates records and tracks
commercial technology build-out
 Electronic filing, using simple Internet form and authorizing nominal
(<$500), partially-refundable charge per link, to cover coordination
and licensing fees
 Form specifies new station’s GPS coordinates, height AGL, and
ground elevation; Transmitter frequency, polarization, and power;
Antenna gain and EIRP

Coordination procedure includes geographical
mapping and charting with government access for
coordinated planning
 Cleared third-party coordinator maintains path database and
geographical path maps (IRAC and NTIA-accessible), automatically
updated with electronically-filed proposals, providing automated
interference analysis based upon path proximities
L1011-V/4-14
Loea Communications Corp.
Mapping Database Example
MMW Wireless Point-to-Point Path Coordination and FCC License Application
Link Identifier *
Transmitter 1
Tx 1 Location
Transmitter 2
Tx 2 Location
(provide data in all fields marked * )
Empire State Building to Sheraton Meadowlands Conference Center, 6.6 miles
Center Frequency *
(GHz)
71.875
Bandwidth *
(MHz)
1750
Antenna Gain *
(dBi)
51.0
EIRP *
(dBW)
36.0
Polarization *
Station Identifier (coordinator use only)
Horizontal
WC2XPB
GPS (NAD83)
Ground Elevation * Tower Height *
Latitude (N) *
Longitude (W) * (ft above sea level)
(ft AGL)
40.7480
73.9841
28
1461
Center Frequency *
(GHz)
73.875
Bandwidth *
(MHz)
1750
Antenna Gain *
(dBi)
51.0
EIRP *
(dBW)
36.0
GPS (NAD83)
Ground Elevation * Tower Height *
Latitude (N) *
Longitude (W) * (ft above sea level)
(ft AGL)
40.8066
74.0773
22
252
Street Address *
or other Locality Identifier
350 Fifth Avenue, New York, NY 10118
Polarization *
Station Identifier (coordinator use only)
Vertical
WC2XPC
Street Address *
or other Locality Identifier
2 Meadowlands Plaza, East Rutherford, NJ 07073
Government Service
Commercial Service
L1011-V/4-15
Loea Communications Corp.
MMW Link Installations in Progress
at Pacific Missile Range Facility
KOKEE RIDGE
Funded Through ONR
Contract (7 miles)
MAKAHA RIDGE
Pacific Missile Range Facility
at Barking Sands
Funded Through NAVAIR
Contract (12 miles)
KAUAI TECH
CENTER, WAIMEA
Phase I
Phase II
L1011-V/4-16
Loea Communications Corp.