 New
Wave Instruments has been the
leading manufacturer of PN sequence (PRBS)
generators for over two decades. Our generators
are used in laboratories, factories, and
universities throughout the world for spread
spectrum and CDMA research, product development,
and system test.Satisfied
customers include such outstanding organizations
as General Electric, Bell Atlantic, NYNEX, Boeing
Aerospace, Lockheed, and Johns Hopkins Applied
Physics Laboratory. International customers
include Fujitsu, Mitsubishi, Sanyo, and Samsung.
Our generators,
which support both DSSS and FHSS spread spectrum,
are being used in a broad range of applications,
including the development of CDMA and WCDMA
cellular communication technology, personal
communications services (PCS), wireless LANs
(WLAN), military reconnaissance, and
communications intelligence (COMINT) equipment.
A number of
models are available, ranging from a convenient
16-stage desktop generator, to a dual 32-stage
rack-mount generator with GPIB capability. Brief
descriptions of the generators are presented on
our Products page,
while detailed brochures and application notes
are available on our Literature page.
Why
Spread Spectrum?
Patented
by a glamorous Hollywood movie star in
the midst of World War II, spread
spectrum remained a classified military
secret until the 1970s. Even then it was
known to only a handful of engineers
until the late 1980s. And yet, just a
decade later, spread spectrum became one
of the hottest topics in wireless
communications!
Exactly
what is spread spectrum, and what makes
it so special?
Simply
put, spread spectrum is a method by which
a narrowband radio signal is spread out
to a much wider bandwidth before
transmission takes place. Upon reception
of the signal, the receiver recovers the
original narrowband signal through a
reverse process, naturally referred to as
despreading. Spreading and despreading
can be accomplished in many ways, but are
usually done using one of two common
techniques, direct sequence and frequency
hopping.
In
direct sequence, the radio signal is
multiplied by a pseudo-random bit
sequence (PRBS) whose bandwidth is much
greater than that of the signal itself,
thereby spreading its bandwidth. In
frequency hopping, the pseudo-random
sequence is used to move the radio signal
about, in a random fashion, across a
broad frequency band.
Regardless
of the spreading technique used, the
purpose for doing so is to exploit one or
more of the many benefits of spread
spectrum: Interference rejection, signal
hiding, frequency band sharing
(code-division multiplexing), anti-jam
properties, and FCC Part 15
license-free operation of up to 1 watt.
Interestingly,
as exotic as spread spectrum may sound,
most everyone has routinely and
unwittingly been enjoying its benefits
for decades, and were doing so long
before the technology was declassified.
The ubiquitous FM radio transmitter
spreads audio signals by a factor of
about ten, thus providing relatively
noise-free reception when compared to the
older AM radio technology.
|
|
SS
Buzzwords!
What's
the buzz in spread spectrum camps? Check
it out with our new QuickGlossary:
Other
Resources
Spread
Spectrum Resources
RF
Resources
RF
Instruments
Friends
of New Wave Instruments
|
Popular
Spread Spectrum & CDMA Sites
|
|
|
Relevant
Search Terms
For the
benefit of those searching the Web,
following are search terms relevant to
this page:
| Spread
Spectrum Topics: CDMA
Technology, Direct Sequence CDMA
(DS-CDMA), Gold Code Generators,
Gold Codes, JPL Code Generators,
JPL Codes, PN Code Generators, PN
Codes, PN Generators, PN Sequence
Generators, PN Sequences, PRBS,
Pseudo-Noise Code Generators,
Pseudo-Noise Codes, Pseudo-Noise
Generators, Pseudo-Noise
Sequence, Pseudo-Random Binary
Sequence, Pseudo-Random Bit
Generators, Pseudo-Random
Sequence, Pseudorandom Binary
Sequence, Pseudorandom Bit
Stream, Pseudorandom Sequence
Generators, Pseudorandom
Sequences, Spread Spectrum
Modulation, Spread Spectrum
System, Spread Spectrum Systems,
Spread Spectrum Technique, Spread
Spectrum Techniques, Spreading
Code, Spreading Codes
RF
& Microwave Topics:
Communication,
Communications
Resources:
Product,
Products, Test Equipment
British
Equivalents:
None
|
|
|
