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Radio Frequency Allocation Chart



Anechoic Chambers




RF Amplifiers


EMC Antennas


Antenna Impedance

Most connectorized RF and/ microwave devices have an impedance of 50 W. Free space (generally the transmission media) has an impedance of 377 W. To further complicate matters, most antennas have a free space impedance of their own (a helix 140 W and wave dipole 70 W). The most efficient transfer of power occurs when the antenna matches the transmission media and/or source impedance. Not all sources are 50 W (CATV is 75W and wave-guide 377 W) and not all impedance is real but for explanation purposes we will use a real impedance of 50 W and ignore imaginary contributions.

Matching the antenna and transmission line to the source impedance is important for a transmitter. The most accepted description of that match is the Voltage Standing Wave Ratio of VSWR. A perfect match is 1.0:1, which indicates the source and load impedance are the same. A bad match depends on the application. For very high power applications (EW systems, radar, radio/television transmitters) anything over 1.5:1 may be unacceptable. Wide band test antennas may have a VSWR of 3.5:1 or more. The ratio describes how much power will be transmitted into the antenna and how much power will be reflected back to the source (see table B-1). The VSWR is then an indication of the efficiency of an antenna. An antenna, which has a poor match, will not be an efficient radiator but an antenna with a good match is not necessary an efficient radiator.

Mismatch Effects


Antenna Impedance W

 Gain Reduction


Gain Reduction

(10 dB antenna)




0 dB


75, 33


.20 dB


100, 25


.51 dB


150, 16.67


1.28 dB


250, 10


2.59 dB


500, 5


4.81 dB

In addition to matching the impedance, most transmission sources have coaxial outputs.  This type of connector has a grounded shield surrounding the center conductor, which carries the RF/Microwave energy.  Many antennas are balanced and both sides of the transmission line are active (such as 300 W twin lead for radio and television).  This requires that not only the impedance be transformed but that the unbalanced coax transmission line is transformed into a balanced condition prior to connection to the antenna.  The device that accomplishes this is generally referred to as a balun.  It is important to note that the best match is obtained with a dummy load, which does not generally radiate at all.  This leads to the next topic, efficiency


Gain is a widely used parameter directly measurable by substituting an antenna with known gain (generally a gain reference antenna) in for an antenna under test (AUT). The output levels of the AUT and the gain reference can then be measured for the same incident field. The gain can then be determined by comparing those measured levels. Gain of an antenna is expressed in dB, 10log10(numerical gain), which is generally referenced to an isotropic radiator (radiates equally in all directions) and expressed as dBi. Typical gains are listed in table 2. The gain expressed for an antenna is generally the maximum or peak gain. This leads to the second part of the gain equation, directivity.

A directional antenna will have a beam that is concentrated in one direction. A typical directional antenna is a standard gain horn with a HPBW of about 20 (in both elevation and azimuth). A highly directional dish antenna may have a HPBW as small as 0.5 in both elevation and azimuth. It is important to note that the HPBW and gain of an antenna are inversely proportional. For the above antennas, the gain for the omni-directional is 2 dB, for the horn 18 dB and for the dish 48 dB. A reasonable formula that relates HPBW and gain is:

Gain (dB) ~ 10 log10 (31,000 / HPBWE X HPBWA)


Several examples of typical antenna gains and HPBW are listed in table B, typical antenna gains and beam-widths. 

Antenna Efficiency

Antenna efficiency is a complicated and often misused figure. All antennas suffer from losses. A simple horn antenna for example will not be as efficient as a perfect aperture of the same size because of phase offset. The real efficiency of an antenna combines impedance match with other factors such as aperture and radiation efficiency to give the overall radiated signal for a given input. The best and most widely used expression of this efficiency is to combine overall efficiency with directivity (of the antenna) and express the efficiency times directivity as gain.


Table B, Typical Antenna Gains and Beam-widths

Antenna Type


Half Power

Beam Width

Typical Gain (dB)






Comm, Test



Helix, 4-turn

EW, Comm, Test



Helix, 6-turn

EW, Comm, Test



Helix, 10-turn

EW, Comm, Test



Std. Gain Horn

EW, Comm, Test



Optimum Horn

EW, Comm, Test



Small Dish

EW, Comm, Test



Large Dish

EW, Comm, Test



The directivity of an antenna is generally combined with efficiency and expressed as gain as described above. The Half Power Beam Width (HPBW), of an antenna, is an expression, in degrees, of the width of the radiated beam between the half-power or 3 dB points (down from the peak of the beam). Many antennas will exhibit one HPBW in azimuth and a different HPBW in elevation written as HPBWA and HPBWE. An antenna described as omni-directional will have equal coverage in all directions. A typical wide band omni-directional (in azimuth) antenna will have a HPBWA of 360 and HPBWE = 50

Other Important Antenna Specifications and Definitions
Side lobe level- This specification is generally given as a maximum value or not to exceed envelope of maximum side lobe level vs. azimuth. The maximum side lobe level is often dictated by the FCC (or similar agency) for transmit antennas that could interfere with other systems if the side lobe levels were excessive.

Front-to-back ratio- Often listed in dB, this specification is the difference between the peak gain of the antenna and the radiation in the back of the antenna (often 180 from the peak of the beam).

RDP (Radiation Distribution Pattern)- This is a complete antenna set of antenna patterns generally taken at intervals of 2x2. The RDP allow for the 3-D reconstruction of the radiation pattern.

Coherent Measurements- The measurement of phase and amplitude verses angle for the antenna measurement. Measurement of orthogonal linear polarizations and the phase difference between them allows for the reconstruction of and incident polarizations.

The polarization of an antenna is the orientation of the transmitted (or received) electric field (E field). The optimum polarization for a system depends on the polarization of other antennas in the system. An infinite number of polarizations exist but the most common are linear and circular. For a linear antenna three possibilities generally are seen vertical, horizontal and slant linear. It is important to match linear polarizations for transmit and receive sites. A linear polarization mismatch can result in up to a 20 dB loss (for cross-linear polarization).

Circular polarization is generally given as right hand circular polarization (RHCP) or left hand circular polarization (LHCP). To determine the polarization of a circular antenna, use the right hand rule. Point the thumb of your right hand in the direction of propagation and curl your fingers. If your fingers point in the direction of propagation, the antenna is RHCP (otherwise it is LHCP). Polarization mismatch loss for circular antennas can also be up to 20 dB (for opposite sense polarization). One technique often used in telemetry systems monitoring aircraft is to use a circular terrestrial receive antenna and a linear transmit on the aircraft. This results in a mismatch loss of about 3 dB (linear to circular) but allows the aircraft to maneuver without causing the link to suffer large mismatch losses caused by cross polarization.

EMC / RFI Filters

EMI / RFI Receivers



Standard Connection Speeds

Data Rate

(Bits / Second)




TAT-1 51-calls 1956 The first transatlantic coaxial telephone cable, 7,802km Out-of-service retired 1978
Bell 103 300bps 1965 Asynchronous data transmission, full-duplex, 2-wire dialup or leased line.
CCITT V.21 300bps 1965 The standard for full-duplex communication at 300 baud in Japan and Europe.
Dataphone 300bps 1958 1st Modem: Bell Labs, Hayes AT commands.
Bell 212a 1.2K 1988 Synchronous - asynchronous data transmission, full-duplex operation, 2-wires.
ITU V.22 1.2K 1988 Standard protocol for transmitting data on telephone lines
Cat1 1.2K 1985 Basic telephone wire, Voice Only
Category 1 1.2K 1985 Basic telephone wire, Voice Only
1,200 baud 1.2K 1962 2nd Modem speed. Basic telephone line transmission rate
POTS 1.2K 1877 Plain Old Telephone Service, the first commercial telephones
ITU V.22bis 2.4K 1988 Standard protocol for transmitting data with telephone lines.
2,400 baud 2.4K 1980 3rd Modem speed
ITU V.29 9.6K 1988 Standard protocol for transmitting data with telephone lines
ITU V.32 9.6K 1991 Standard protocol for transmitting data with telephone lines
Facsimile 9.6K 1980 FAX Machines / FAX Modems
9,600 baud 9.6K 1984 4th Modem speed
ITU V.32bis 14.4K 1991 Standard protocol for transmitting data with telephone lines
14,400 baud 14.4K 1991 V.32bis Modem, V.17 fax
UART 8250 19.2K 1981 Universal Asynchronous Receiver-Transmitter, 0-byte buffer.
RS-232 20.0K 1987 50ft, Serial Port, single-ended data transmission
RS-366 20.0K 1988 Uses RS-232 electrical specs, different connector pin outs and signal functions.
28,800 baud 28.8K 1994 V.34, Rockwell V. Fast Modems
GeoPort 28.8K 1996 A serial port for Apples that provides interface between telephone and computer
33,600 baud 33.6K 1996 Maximum data transmission rate with copper telephone wires.
ITU V.34 ( 36.6K 1998 Standard protocol for transmitting data with telephone lines
UART 16450 38.4K 1995 Universal Asynchronous Receiver-Transmitter, 1-byte buffer.
K56flex 48.0K 1998 V.90, Proprietary protocol By: Lucent Technologies
X2 48.0K 1998 V.90, Proprietary protocol By: US Robotics
Modem, Analog 48.0K 1958 MOdulator - DEModulator, sends at 33.6K, receives at 48K
ITU V.90 56.0K 1998 Standard protocol for transmitting data with telephone lines
Modem, Digital 56.0K 1990 MOdulator - DEModulator, sends at 56K, receives at 56K
HSCSD 57.6K 1999 High Speed Circuit Switched Data, (wireless)
DS-0 64.0K 1962 Digital Signal Level 0, 1 Channel (1/24 of T1)
E-0 64.0K   1 Channel, Europe & Japan
J-0 64.0K   1 Channel, Japanese
N-ISDN 64.0K 1976 Narrowband Integrated Services Digital Network
RS-423 100.0K 1995 4000ft, Single-ended data transmission
GPRS 114.0K 1999 General Packet Radio Service, RF in space (wireless)
Modem, Null 115.2K 1987 Special cable allowing two computers to communicate with RS-232 ports.
PS/2 115.2K 1987 By IBM for keyboards and pointing devices.
RS-232e 115.2K 1987 50ft, Serial Port, single-ended data transmission
UART 16550 115.2K 1995 Universal Asynchronous Receiver-Transmitter, 16-byte buffer.
ISDN-BRI 128.0K 1980 BRI (Basic Rate Interface) 2x64K B-channels, 1x64K D-channel
Euro-ISDN 144.0K 1993 128K usable. Allows full transparent inter-working between all European countries
Parallel Port 150.0K 1981 IBM's first printer port.
LocalTalk 230.0K 1983 300m Apple Computer's AppleTalk networking scheme.
MAX3100 230.0K 1997 Multi-drop communication technique known as 9-bit mode. the world's smallest UART
EDGE 384.0K 2000 Enhanced Data GSM Environment. Global System for Mobile (GSM) wireless service.
Satellite Dish 400.0K 1957 RF in space, wireless WAN, sends at 33.6K, receives at 400K
UART 16650 460.8K 1995 Universal Asynchronous Receiver-Transmitter, 32-byte buffer.
UART 16750 921.6K 1995 Universal Asynchronous Receiver-Transmitter, 64-byte buffer.
1Base5 1.000M 1986 250 Meters Two pairs of twisted telephone cable.
StarLAN 1.000M 1970 250 Meters Two pairs of twisted telephone cable.
B-ISDN 1.500M 1988 Broadband Integrated Services Digital Network
G.lite 1.500M 1998 18000 feet Asymmetric Digital Subscriber Line, sends at 512K, receives at 1.5M
IDSL 1.500M 1997 18000 ft, DSL over ISDN, sends 64K-1.5M, receives 1.5-9M
Modem, Cable 1.500M 1997 Sends at 3M, receives at 1.5M.
DS-1 1.544M 1975 Digital Signal Level 1, 24 Channels (1xT1)
HDSL 1.544M 1991 12000 ft, High bit-rate DSL, sends at 2.048M, receives at 1.544M
SDSL 1.544M 1998 12000 ft, Symmetric DSL, sends at 2.048M, receives at 1.544M
T-1 1.544M 1957 Trunk Level 1, 24 Channels (1xT1) Time-Division Multiplexing By: AT&T
ISDN-PRI 1.544M 1988 Primary Rate Interface 23x64K B-channels, 1x64K D-channel on T1, 23B+D
J-1 1.544M   24 Channels, Japanese
RS-449 2.000M 1970 1km, Serial binary data interchange
Twinax 2.000M 1980 4000 ft, Unike coax has 2 conductors in center.
E-1 2.048M 1997 30 Channels, Europe & Japan, 1.920M usable
Euro ISDN-PRI 2.048M   Primary Rate Interface 30x64K B-channels, 1x64K D-channel on E1, 30B+D
ARCnet 2.500M 1968 Attached Resource Computer Network By: Datapoint.
OX16C952 3.000M 1992 The newest and fastest PC UART, the deepest FIFOs 128-byte buffer.
DS-1c 3.152M 1985 Digital Signal Level 1c, 48 Channels (2xT1)
J-1c 3.152M   48 Channels, Japanese
T-1c 3.152M 1985 Trunk Level 1c, 48 Channels (2xT1) Time-Division Multiplexing
UMTS 3.500M 1998 Universal Mobile Telephone System or often referred to as 3G
Cat2 4.000M 1990 1Mhz Used for Apple computer's LocalTalk
Category 2 4.000M 1990 1Mhz Used for Apple computer's LocalTalk
IrDA 4.000M 1994 Infrared Data Association, wireless communication standard
DS-2 6.312M 1969 Digital Signal Level 2, 96 Channels (4xT1)
J-2 6.312M   96 Channels, Japanese
T-2 6.312M   Trunk Level 2, 96 Channels (4xT1) Time-Division Multiplexing
ADSL 8.000M 1997 Asymmetric DSL, sends at 1.500M, receives at 8.000M
E-2 8.448M   120 Channels, Europe & Japan
10Base-T 10.000M 1995 100 meters, Ethernet (Unshielded Twisted Pair) Cat3
10Base-2 10.000M 1985 185 meters, (Cheapernet) Thin Net Ethernet 50 ohms Thin Coaxial
10Base-5 10.000M 1985 500 meters, Thick Net Ethernet 50 ohms (Thick Coaxial)
10Base-F 10.000M 1993 2000 meters, (fiber-optic)
10Broad36 10.000M 1985 3600 meters, Ethernet specification using broadband coaxial (CATV) cable.
Cat3 10.000M 1991 16MHz Voice Grade twisted-pair wire.
Category 3 10.000M 1991 16MHz Voice Grade twisted-pair wire.
CAIS bus 10.000M 1991 Common Airborne Instrumentation System, a transformer coupled comm. link.
DECnet PhaseIV 10.000M 1983 First released by Digital in 1983 for its VMS and RSX-11 systems.
RS-422a 10.000M   4000ft, Differential Data Transmission
RS-485 10.000M   4000ft, Balanced line interface, 2-wire, half-duplex, differential.
RS-530 10.000M   30km, fiber-optic Point to Point
Standard SCSI 10.000M 1995 SCSI-1,Small Computer System Interface
Wireless LAN 11.000M 1997 Ethernet performance for use within premises and zones. 802.11 technologies
USB 1.1 12.000M 1996 5 meters, Universal Serial Bus, external bus standard
Token Ring 16.000M 1982 LAN, a type of computer network
EIDE 16.600M 1993 Enhanced Integrated Drive Electronics
ARCnet Plus 20.000M 1992 Attached Resource Computer Network
Cat4 20.000M 1990 20MHz Twisted-pair wire, Token Ring
Category 4 20.000M 1990 20MHz Twisted-pair wire, Token Ring
Fast Wide SCSI 20.000M 1986 1.5m, Small Computer System Interface
MCA 20.000M 1987 Micro Channel Architecture
ECP/EPP 24.000M 1994 High performance bi-directional parallel port.
ATM-25 25.600M 1991 Asynchronous Transfer Mode, uses fixed length packets called cells.
ZV-Port 27.000M 1996 Zoomed Video via PCMCIA bus to VGA controller.
J-3 32.064M   480 Channels, Japanese
EISA 33.000M 1982 Extended Industry Standard Architecture
E-3 34.368M   480 Channels, Europe & Japan
Ultra SCSI 40.000M 1993 SCSI-3, Small Computer System Interface
VMEbus 40.000M 1980 Industrial controls: factory automation, robotics, etc.
VSAT 40.000M 1958 Very Small Aperture Terminal Satellite Communication, antenna of 1.8 meter dia.
DS-3 44.736M 1972 Digital Signal Level 3, 672 Channels (28xT1)
T-3 44.736M 1991 Trunk Level 3, 672 Channels (28xT1) Time-Division Multiplexing
V-ADSL 51.000M 1995 51.00M at 1000 feet & 25.600Mbps at 3000-4000 feet
STS-1c 51.840M 1986 Synchronous Transport Signal, Level 1
OC-1c 51.840M   Optical Carrier Level 1, fiber-optic, 672 Voice Circuits
VDSL 52.000M 1995 Very high speed DSL, send 1.5-2.3M, receive 13-52M
HSSI 53.000M 1989 50 ft, High-Speed Serial Interface
DS-3c 89.472M   Digital Signal Level 3c, 1344 Channels (56xT1)
T-3c 89.472M   Trunk Level 3c, 1344 Channels (56xT1) Time-Division Multiplexing
J-4 97.200M   5760 Channels, Japanese
J-3c 97.728M   1440 Channels, Japanese
100Base-F 100.000M 1984 Fast Ethernet with fiber-optic Cable.
100Base-T 100.000M 1993 100 meters, Fast Ethernet (Unshielded Twisted Pair) Cat5
100Base-T2 100.000M 1991 Fast Ethernet (2-pairs of normal-quality twisted-pair wire) Cat3
100Base-T4 100.000M 1991 100 meters Fast Ethernet (4-pairs of normal-quality twisted-pair wire) Cat3
100Base-TX 100.000M 1993 220 meters, Fast Ethernet (Unshielded Twisted Pair) Cat5
100VG-AnyLAN 100.000M 1997 200 meters, Voice Grade Cat3+ on Any LAN
Cat5 100.000M 1993 100MHz, Unshielded twisted-pair wire, Fast Ethernet
Category 5 100.000M 1993 100MHz, Unshielded 4 twisted-pair wire, Fast Ethernet, RJ-45 connector.
CDDI 100.000M 1993 Copper Data Distribution Interface, the copper version of FDDI
FDDI 100.000M 1993 Fiber Distributed Data Interface, uses a token ring protocol.
Cat7 100.000M 1997 600Mhz, Unshielded twisted-pair wire (standard pending)
Category 7 100.000M 1997 600Mhz, Unshielded twisted-pair wire (standard pending)
FibreChannel 125.000M 1988 fiber-optic-based, computer peripheral architecture.
DS-3d 135.000M   Digital Signal Level 3d, (87xT1) By: AT&T
T-3d 135.000M   Trunk Level 3d, (87xT1) Time-Division Multiplexing
E-4 139.264M   1920 Channels, Europe & Japan
ESCON 150.000M 1996 Enterprise Systems Connection - A star topology invented
STM-1 155.520M   Synchronous Transport Module, Level 1
STS-3c 155.520M 1986 Synchronous Transport Signal, Level 3
OC-3c 155.520M   Optical Carrier Level 3, fiber-optic, 2016 Voice Circuits
AGP 2.0 266.000M 1998 Accelerated Graphics Port
DS-4 274.176M 1976 Digital Signal Level 4, 4032 Channels (168xT1)
T-4 274.176M   Trunk Level 4, 4032 Channels (168xT1) Time-Division Multiplexing
FireWire 400.000M 1995 A serial SCSI variant developed by Apple
STM-3 466.560M   Synchronous Transport Module, Level 3
STS-9c 466.560M 1986 Synchronous Transport Signal, Level 9
OC-9c 466.560M   Optical Carrier Level 9, fiber-optic, 6048 Voice Circuits
USB 2.0 480.000M 1999 Universal Serial Bus, external bus standard v2.0
PCI 2.2 533.000M 1993 Peripheral Component Interconnect
TPC-4 560.000M 1992 Trans-Pacific Cable 4, Vancouver Island & Manchester, CA on the Pacific Ocean.
TAT-8 565.000M 1988 fiber-optic cable network laid from Tuckerton NJ to England and France.
TAT-9 565.000M 1991 fiber-optic cable network laid from North America to Europe.
TAT-10 565.000M 1992 fiber-optic cable network, links United States with Germany and The Netherlands.
TAT-11 565.000M 1993 France Telecom, fiber-optic cable network from Manahawkin to England and France.
TAT-12 565.000M 1996 1st fiber-optic cable network to operate as a fully backed-up "self-healing" cable loop.
TAT-13 565.000M 1996 2nd fiber-optic cable network to operate as a fully backed-up "self-healing" cable loop.
E-5 565.148M   7680 Channels, Europe & Japan
ATM 622.000M 1988 Asynchronous Transfer Mode
STM-4 622.080M   Synchronous Transport Module, Level 4
STS-12c 622.080M 1986 Synchronous Transport Signal, Level 12
OC-12c 622.080M   15000 meters Optical Carrier Level 12, fiber-optic, 8064 Voice Circuits
OC-18c 933.120M   Optical Carrier Level 18, fiber-optic, 12096 Voice Circuits
1000Base-CX 1.000G 1998 25 meters 2-pair 150 ohms STP, Gigabit Ethernet, copper cable.
1000Base-F 1.000G 1996 Gigabit Ethernet with fiber-optic Cable.
1000Base-LX 1.000G 1998 550 meters Gigabit Ethernet, long wavelength laser transmitters, fiber-optic cable.
1000Base-SX 1.000G 1998 5000 meters Gigabit Ethernet, short wavelength laser transmitters with fiber-optic cable.
1000Base-T 1.000G 1999 100 meters Gigabit Ethernet, four pairs of 100-ohm Cat5 or better cable
1000Base-X 1.000G 1998 Gigabit Ethernet, with twisted pair cable.
Ethernet 1.000G 1976 10M to 1000M
PCI-X 1.000G 1999 133 MHz Industry-standard I/O interconnect
WidebandATM 1.000G 1996 Gigabit Ethernet with fiber-optic cable.
PC150 SDRAM 1.200G 2000 PC150 Synchronous DRAM
OC-24c 1.244G   Optical Carrier Level 24, fiber-optic, 16128 Voice Circuits
DRDRAM 1.600G 1999 Direct Rambus Dynamic Random Access Memory
HIPPI-PH 1.600G 1987 High-Performance Parallel Interface physical layer
RDRAM 1.600G 1999 Rambus Dynamic Random Access Memory
SLDRAM 1.600G 1997 Synchronous Link Dynamic Random Access Memory
QuickRing 1.700G 1992 A high speed point-to-point data transfer architecture from Apple
OC-36c 1.866G   Optical Carrier Level 36, fiber-optic, 24192 Voice Circuits
SDRAM 2.100G 1996 Synchronous Dynamic Random Access Memory
SciNet 2.325G 1995 fiber-optic, part of the vBNS backbone
Cat6 2.400G 1999 250MHz, Cable standards under development
Category 6 2.400G 1999 250MHz, Cable standards under development
SONET 2.488G 1988 Synchronous Optical NETwork-Designed by the telcos.
STM-16 2,488G 1997 Synchronous Transport Module, Level 16
STS-48c 2,488G 1986 Synchronous Transport Signal, Level 48
OC-48c 2.488G 2000 Optical Carrier Level 48, fiber-optic, 32256 Voice Circuits
SERDES 2.500G 1993 SERializer/DESerializer ASIC transceiver core By: Texas Instruments
InfiniBand 2.500G 2000 Next Generation I/O
vBNS 2.500G 1986 Very high-speed Backbone Network Service
OC-96c 4.976G   Optical Carrier Level 96, fiber-optic, 64512 Voice Circuits
CANTAT-3 5.000G 1994 Cable to Nova Scotia via Iceland & Faroes, Northern England, Denmark & Germany.
FLAG 5.300G 1997 Fiber-optic Link Around the Globe, 27,300km linking Great Britain and Japan.
OC-192c 9.953G 2000 Optical Carrier Level 192, fiber-optic, 129024 Voice Circuits
LDT bus 12.000G 2001 AMD's Lighting Data Transport bus.
RoX-II bus 12.800G 1998 (Ring Of Switches) bus architecture
OC-256 13.271G   Optical Carrier Level 256, fiber-optic, 172032 Voice Circuits
DDRSDRAM 16.800G 2000 Double Data Rate Synchronous Dynamic Random Access Memory
OC-768 39.813G 2002 Optical Carrier Level 768, fiber-optic, 516096 Voice Circuits
OC-3072 159.252G   Optical Carrier Level 3072, fiber-optic, 2064384 Voice Circuits
TAT-14 640.000G 2000 France Telecom, fiber-optic cable network spans 15,428 kilometers.
DWDM 2.56T 2002 2500 miles, 64-channel Dense Wave Division Multiplexing
Glass 75.00T 1880 Light through glass fiber-optic cables.



Protocol MB/s
 IrDA-Control 0.009
 Bluetooth 1.1
 Bluetooth 2
2 to 12
 USB 1.1
 USB 2.0
 Fast SCSI 2
 Fast Wide SCSI 2
 Ultra SCSI
 Ultra Wide SCSI
 Ultra2 SCSI
 Ultra 160 SCSI
 FireWire (IEEE 1394)
 FireWire (IEEE 1394b)





 Last Updated: July 24, 2017

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An Electro Mechanical Research and Development (EMRAD) Corporation, Company


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