MAXIM Integrated Products, Inc., Sunnyvale, CA has released several new noteworthy Silicon Chips and Chipsets.
Their new PWT1900 Chipset is intended for PCS Phone and WLL apllications where TAG-6 and / or DECT standards are used.
They also announced the MAX2511 wide dynamic range IF transceiver chip and the low cost MAX26XX family of 1 GHz RF
Amplifiers with shutdown and bias control. For more info check their WEB site at: http://www.maxim-ic.com
ROOT Inc., Tokyo, Japan has released its RZ95001 model 2.4 GHz ISM band SS Data Communication Modem. Using the
STEL-2000A the radio is capable of up to 2 Mbps in burst mode packet wireless communications. For more info check
their WEB site at: http://www.root-hq.com
OTC Telecom's AirEZY 900 MHz SS products are now available off the shelf in "bubble pack" form at NCA and other
Silicon Valley merchants. Apparently OTC thinks that consumers should have easy access to their SS products. For
more info check their WEB site at: http://www.ezylink.com/
Even though PROXIM of Mountain View, CA has had trouble with getting acquired, it continues to make strategic
alliances with key industry players. They recently were selected by HBO & Company to supply 2.4 GHz Wireless SS
technology for the healthcare industry. PROXIM also made a deal with Data General Corporation using the RangeLAN2
for future mobile computing systems. For more info check their WEB site at: http://www.proxim.com/
AVISTA DESIGN SYSTEMS of Folsom,CA recently released version 1B of their Avista Spectra/XL analog circuit
design / simulation software. This very capable software performs a "what if" function for many demanding linear
and non-linear circuit simulations under the Microsoft EXCEL spreadsheet. In their December 5, 1996 issue, EDN
magazine announced the "Hot 100 Products of 1996" based on tracking data from their readers. This software was
selected for this "best of the best" list of innovative products. Also in the December 1996 issue, EE Product
News announced the "Products of the Year" selected as the "best in terms of technological
advancement, price/performance, applications potential..." from tens of thousands of new product announcements. Avista Design Systems'
Spectre/XL software was selected for the CAE/CAD Software category. For more info check their WEB site at:
http://www.avista.com AVISTA has also announced the soon to be released
VISIO TECHNICAL software for schematics and simulation -- for more info on VISIO check their WEB site at:
Stanford Telecom, Sunnyvale, CA recently introduced the STEL-9258 board-level next generation VSAT broadband
receiver. For more info check their WEB site at: http://www.stelhq.com/
Strategies Unlimited of Mountain View, CA just released a new study report on the GaAs Device Market that forecasts
the business to exceed $2 billion in the year 2000. For more information or to order the report email Mr. George Bechtel,
Director, Wireless Program at: email@example.com.
Go DSP, Toronto, Ontario, Canada has released its CODE COMPOSER software for DSP software development. This powerful
DSP development environment makes it easy to develop, de-bug and test new DSP code for a variety of platforms. For more
info check their WEB site at: http://www.go-dsp.com/
Here it is -- our THIRD online issue! Of course, we're a little late (again) with it! Better late than never they say. . . .
Randy Roberts, Editor & Publisher, SSS Online Director, RF/SS Consulting
ANNOUNCING THE 1997 UNIVERSITY OF OXFORD SUMMER ENGINEERING PROGRAMME
Following the success of the 1996 Programme, the University of Oxford's
Department for Continuing Education and the Department of Engineering
Science are offering the 9th annual Summer Engineering Programme.
Each year a selection of short courses on state-of-the-art engineering
topics are presented.
The 1997 Programme includes short courses in the fields of Digital
Communication Systems; Wireless Communication Technology;
Electronic Circuits and Systems; Electronic Packaging; Optical
Engineering and Non-Technical, Professional Development.
This year's Programme includes presentations from University of Bristol;
University of California, USA; University of Surrey; Motorola European
Cellular Infrastructure Division; Racal Research; Bell Labs, USA; Signal
Consulting Inc, USA; GEC Plessy; AmeriCom Services; Question and
Express Packaging Systems Inc, USA. There are contributions also
from DigiMedia Vision; Hewlett Packard; Loughborough Sound Images;
Plextek Ltd; BBC; University of Liverpool; University of Pennsylvania;
Securicor Radiocoms; Aethos; GMMT; KU Leuven-Belgium and
All courses are designed for participants who are graduate level
engineers and scientists in industry and are being held between
Thursday, 29 May and Friday, 11 July 1997.
Courses will be held at the Department for Continuing Education, the
Department of Engineering Science, St Annes College and Regents
Park College. Delegates will be offered accommodation in the
residential centre belonging to the Department for Continuing
Education and in local Oxford hotels.
A detailed brochure with further information on the courses is available
now. Please write, telephone, fax or e-mail:
Continuing Professional Development Centre
Department for Continuing Education
67 St Giles
AMI Adds New High Data Rate ICs to the WavePlexTM Family of
POCATELLO, Idaho - March 24, 1997 - American Microsystems, Inc. (AMI),
a leader in application specific solutions and wireless ICs, unveiled the
newest additions to their popular WavePlex family of wireless integrated
The SX049 Spread Spectrum Transceiver, the SX048 Spread Spectrum
Receive-Only and the SX047 Spread Spectrum Transmit-Only are the first
direct sequence spread spectrum (DSSS) ICs developed by AMI
specifically for higher data rate wireless applications.
Security systems, subway train platform monitors, remote medical
systems and oil and mining applications are just a few of the many data,
voice and video applications that will benefit from these high data rate
The SX049 is a high performance, high data rate transceiver containing
all the baseband circuitry needed to implement DSSS radios. With data
rates from 100 bitslsec (bps) to 16 megabits/sec (Mbps) and PN code
lengths up to 2,047 chips/bit, the SX049 offers more flexibility and
functionality than any other baseband IC.
Designed to serve as a collection host for a large group of WavePlex
transmitters and transceivers, the SX048 features data rates up to 16
Mbps. This highly programmable baseband CMOS IC will simplify the
design of DSSS modems.
Offering data rates up to 8 Mbps, the SX047 is designed to interface
easily with other WavePlex receivers and transceivers. Multiple SX047
nodes can supply data to a single collector host.
"Higher data rate networks with multiple remote sites may need to
monitor individual 'stations' at regular intervals. However, all stations
may not be required to receive information," said Rocke Acree, WavePlex
products manager. "The SX049, SX047 and SX048 provide the flexibility
to meet any network requirement. These high data rate ICs are able to
address the specific function required and together create a customized,
state-of-the-art data communication network."
Available in a 52-lead PQFP package, the SX047 Transmit-Only IC
allows the user to manage internal transmit functions including the type
and length of PN codes, data rates, chipping rates, preamble, transmission
protocols, power levels and type of redundancy checks as well as manage
the external circuitry for signal transmission.
The SX049 Transceiver and SX048 Receive-Only ICs are available in 68-
lead PLCC, 64-lead PQFP and 64-lead TQFP packages. These highly
programmable baseband ICs feature message processor receive circuits
including the receive PN code generator, receive synchronization and
tau-dither tracking loop, integrate dump control, data descrambler, packet
decoder and CRC checker.
Each PN code generator consists of two 11-bit PN generators, allowing
selection of an "A" code, a "B" code, or a "Gold code" combination of the
"A" and "B" codes. These baseband ICs can be programmed and interfaced
through a standard 8-bit microcontroller port and have port FIFOs to ease
data timing on transmission and reception.
Price and Availability
Samples of the SX049 will be available in March 1997, with volume
production scheduled for May 1997. Samples and volume production for the
SX047 and SX048 will follow. Volume pricing, for quantities of
10,000 pieces, is currently projected at $23.05 per unit for the SX049,
$14.65 for the SX048 and $8.80 per unit for the SX047.
AMI celebrates over 30 years of leadership in application specific
solutions through superior semiconductor design and manufacturing
processes. The company, based in Pocateilo, Idaho, provides a full range
of digital and mixed-signal ASICs, CMOS foundry services, application
specific standard products, and high-level integrated solutions through
For more information on AMl's capabilities, write to American
Microsystems, Inc., 2300 Buckskin Road, Pocatello, Idaho 83201, or
see their WEB site at:
Ever wanted to build a simple SS project to learn something about Spread Spectrum and get Get Your Hands Dirty? Well this
project may be just the thing for you. The following text is lifted from our NEW SS How To Page
and is the basis for an upcoming PN Trainer Kit.
A picture of this PN Generator built on a digital breadboard with an internal power supply. The unit shown actually has two of these
universal PN generators on it, for experimenting with PN code correlation characteristics.
This design generates an arbitrary bit stream from 1 to 16 bits long. To simplify the building and tesing of this design,
no programming, no EPROM blowing and no PAL /GAL is required! Just set the desired bit stream length in dip switch S1 and enter
the desired "code" into dip switches S2 and S3, one bit at a time. If you enter a PN code into the dip switches, you get the desired
PN code at the output. Entering any arbitrary, up to 16 bit long bit stream, will also generate an output, even though it may not be
a "real" PN code, since there are no "smarts" provided in this design!
This simple design is based on the old TTL 16 bit multiplexer, the 74150. This part is still available in a few places like Jameco
and JDR, so you should be able to find them. The virtue of using this part is that ANY up to 16 bit pattern can be entered via S2
and S3 -- thus generating ARBITRARY 1 to 16 bit patterns for a variety of tests / experiments with PN codes or other digital sequences.
We used a 10 MHz TTL 14 pin Dip clock in our prototype, however any clock up to about 20 MHz should work here. Go too fast however,
and the 74150 will not keep up!
By the way, the 20 resistor pull ups shown in the schematic below are not at all critical -- use any value between 3.3K and 10K --
but, try to make them all the same value! As shown in the schematic, each IC should have at least one Vcc bypass capacitor of its
own. I used six capacitors total -- more are better! Other details of this circuit are not at all critical, especially at the speeds
U2 is used to divide the frequency of the clock down to 2.5 MHz (or 1/4 of whatever clock you use.) This was done for several reasons,
some of which will be explained later. One reason for dividing the clock down by 4:1 is to keep the PN clock rate low enough so that
low cost, low speed scopes and other test equipment can be used with this design. The 2.5 MHz PN clock gives us a PN "chip rate" of
2.5 MHz or 2.5 MChips per second. The counted down by 4:1 clock drives the 74HC163 - 1 to 16 bit programmable counter. Note that
this counter's length controls the length of the PN stream generated by this design. Just enter the twos-complement of the code
length you want on S1 to set the desired sequence length. Note that no master reset is provided on this design -- so you may need
to power the circuit down and up again to ensure changed settings on the dip switches are properly timed and input to the circuit.
The schematic of this simple design is shown below. You may download the schematic in either ORCAD CAPTURE .DSN or standard .DXF
format by clicking on the appropriate line below the online gif schematic.
A TEK TDS350 Scope picture of the output of this PN Generator. The top trace is the PN stream, the bottom trace is the
sync signal (or PN Epoch). This pic was taken with the scope's Bandwidth limited to 20 MHz.
A TEK TDS350 Scope picture of the output of this PN Generator without using U6 to re-time and cleanup PN and Sync.
The top trace is the U5-pin 10 signal direct, the bottom trace is the U3-pin 15 signal direct. Note that both traces
are noisy and have a few glitches with this setup. U6 was added to give the "cleanest" PN and sync signals possible --
yet retaining the correct timing between PN and Sync (Epoch). This pic was taken with the scope's Bandwidth not limited.
A TEK TDS350 Scope picture of the final output of this PN Generator. The top trace is the PN stream, the bottom trace
is the sync signal (or PN Epoch). This pic was taken with the scope's Bandwidth not limited. Note that whatever noise
or glitches that are present, are ONLY digital sampling scope "artifacts." The PN code set into the dip switches here
is: 010100100110111 -- a 15 bit pattern also known as: 2937HEX. Switch S1
was set for a 1 on its LSB, thus giving a 15 bit long bit stream. Let's try another bit stream: 29B8HEX (or 010100111001000
in binary) -- a Maximal Lebggth Sequence from a 4 bit shift register type PN generator. This pattern is shown below:
A TEK TDS350 Scope picture of the output of this PN Generator with a 15 bit Maximal Linear Sequence output. The top trace
is the PN stream, the bottom trace is the sync signal (or PN Epoch). This pic was taken with the scope's Bandwidth limited to 20 MHz.
This circuit design was specifically put together to be able to build up two (nearly identical) 1 to 16 bit PN generators on the same
prototype board to enable demonstrations, experiments and tests of correlation, cross-correlation and synchronization techniques.
I hope to put together a "PN Training Kit" using this approach that is not only inexpensive, but modular and expandable. This kit will
include the ability to change the divide by 4. in the second 1 to 16 bit PN generator, to allow a divide by 3 / 4 / 5 "Incremental Phase
Modulator" to be implemented for receive PN synch purposes (now you see why we divided the clock by four in our "basic" design). We'll
also provide a VCXO for the second TTL crystal clock. I plan to add both early-late and "Tau Dither" tracking circuitry for baseband PN
tracking loop demonstrations. Stay tuned as this kit develops -- perhaps you have some other ideas about what might be included in
this "PN Trainer?" PLEASE DROP US AN email, IF YOU DO!
For other great Hands-on SS Project ideas, please see our SS How To Page
Questions, comments or suggestions on
anything covered in this column are
welcome. Please feel free to share any
info or special knowledge you may have. Just drop us an email:
Contributions:HAM RADIO SST Block Diagrams
Here is a Detailed Set of Block Diagrams for the Proposed SST Radio for the TAPR SS STA / Next Generation FCC, Part 97 - SS Rules
By Randy Roberts, KC6YJY
Top Level SST Block Diagram
OK all you "SS fans" out there -- here are my very latest thoughts on a modular, low cost SS radio design for Ham Radio. The block
diagram above shows the top level, sort of interconnection view of the new design that I have in mind. After following the TAPR SS SIG
for several months and watching our email from all of you, I have incorporated a few changes to the previous Ham Radio SS schemes.
This design can use either the STEL / ZILOG DSSS baseband chips OR the Harris PRISM baseband chip (HSP3824). Note from the following
block diagrams that almost all of the other chips in the Harris PRISM Chipset are used in this design.
The design is modular and flexible enough to allow "a mix and match" of PCBs to allow Frequency Hop Modulations to be used, as well!
Finally, my favorite SS Modulation -- namely "Hybrid" combined DS / FH is easily accommodated in this design, since the Harris
Dual PLL synthesizer IC (the HFA3524) can switch up to 50 MHz (at 2.4 GHz) in under 400 microseconds!
Please realize that NOTHING in this design, so far, is "locked in concrete!" In other words, we are very open to suggested improvements,
simplifications, etc. This design is intended to overcome some of the criticisms of our previous "ideas" for a Ham Radio SS design.
This design is NO LONGER "band specific" -- even though we have shown a concept here for the 2.4 GHz band. Other IF or RF PCBs can
be designed and accommodated for many other frequency bands. Also, the scheme presented here allows both DS AND FH modulation formats
to be transmitted AND received without worrying about "Band Specific" transverters and their non-linearities, group delay distortions
and similar "little" details.
This is just the very first, small introduction to this design -- I plan to add a lot more design description details and related ideas,
as time permits!
Please take a look at the concepts presented here -- I'd love to hear from you with constructive criticisms and I'd very much like to hear your ideas!
Just drop us an email:
or post something on the TAPR SS SIG:firstname.lastname@example.org -- 73 for now!
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