1. What is TIMS?
2.How does TIMS fit into an electronics engineering course, because in telecommunications we use real applications such as telephone lines, microwaves, satellites, LANS, etc?
3. How does a student or lecturer make experiments with TIMS?
4. How does a student relate TIMS "modules" to block diagrams ? Why are there red and yellow connectors on both sides of each module and why don't gain and adjustment control knobs have calibration or level scale markings?
5. How is TIMS used?
6. Why can TIMS be used by both undergraduate and post graduate students, and lecturers?
7.Describe the TIMS system hardware?
8.What is the difference between BASIC modules and ADVANCED modules?
9 What equipment do I need to use TIMS?
10.How many experiments can you do with TIMS? What kind of experiments can TIMS do?
11. What can I do if a building-block (module) required for a particular experiment is not available?
12. How do you "model" a telecommunications "channel"? (A "channel" is the path or medium along which the modulated or coded message is transmitted. eg. radio waves, coaxial cable, telephone line, etc).
13. How do I learn how to put together experiments - where can I get some ideas?
14. Isn't TIMS just a simple "demonstration" system?
15.What is the Master Signals module?
16.Why is it important that the Master Signals outputs are synchronised?
17. Why is the TIMS "carrier" only 100kHz? Don't you know that in real telecommunications systems, carrier frequencies can range from 1MHz to many tens of Giga Hertz?
18. Can TIMS DSP modules be used with BASIC and ADVANCED modules?
19. What is the difference between the DSP Run Board (TIMS320 DSP-RB) and the DSP Development Board (TIMS320 DSP-DB)?
20.Why does TIMS DSP only use the Texas TMS320C10 DSP chip? Isn't it a waste of time showing students a first generation DSP chip?
21. What is TIMS TRUNKS?
1.What is TIMS?
TIMS is a hardware training system, designed
specifically for telecommunications and signal processing courses, that
requires only an oscilloscope to use the system.
2. How does TIMS fit into
an electronics engineering course, because in telecommunications we use
real applications such as telephone lines, microwaves, satellites, LANS,
etc?
TIMS gives students hands-on experience with
the theories and concepts involved in the specific area of "transmission
theory". "Transmission" involves an original message being carried from
one point to another, using either analog or digital modulation. TIMS will
allow the students to learn about the concepts of the many sub-sections
of a major telecommunications system: eg sampling and reconstruction; coding
and decoding; modulation and demodulation; etc. After a student has learnt
and grasped these fundamental concepts, it is much easier for them to take
this knowledge and apply it to HF electronics, microwaves, telephone lines,
computer local area networks, and so on.
3.How does a student or
lecturer make experiments with TIMS?
Experiments are made by patching together
TIMS modules. Each module represents a fundamental telecommunications system
building block. The block diagram of the text book can be quickly realised
by patching together TIMS modules in accordance with the block diagram.
4. How does a student relate
TIMS "modules" to block diagrams ? Why are there red and yellow connectors
on both sides of each module and why don't gain and adjustment control
knobs have calibration or level scale markings?
All TIMS modules follow a very strict and
consistent "front panel convention". Once a user has been introduced to
the TIMS conventions, they will find it very easy to use any TIMS module.
The TIMS "front panel conventions" ensure that TIMS modules relate very
closely to the Block Diagram representations that are commonly used in
telecommunications and signal processing.
The key conventions are as follows:
(i) TIMS inputs are always on the left hand side of the module's panel.
(ii) TIMS outputs are always on the right hand side of the module's panel.
(iii)Analog ˇ@inputs & outputs are always yellow.
(iv)TTL ˇ@level inputs & outputs are always red.
Gain and adjustment control knobs do not have
scale markings intentionally, as engineering students are expected to measure
the amplitude (using either the CRO or WIDEBAND TRUE RMS METER )and frequency
of each module's output (with the built-in FREQUENCY COUNTER), and relate
or adjust these values in accordance with the block diagram or equation
they are modelling.
TIMS effectively stops the "cookbook" approach
to making experiments.
5. How is TIMS used?
TIMS is used to implement block diagrams,
which are used to model mathematical equations, or the hardware realizations
of telecommunications systems or signal processing schemes.
6. Why can TIMS be used
by both undergraduate and post graduate students, and lecturers?
TIMS is valuable to all these users because
TIMS actually models mathematical equations and telecommunications block
diagrams. TIMS is much more than just a waveform or experimental "demonstration
system".
7. Describe the TIMS system
hardware?
TIMS is comprised of the following system
components:
a) The FIXED UNIT, which includes 7 "fixed modules" and a rack which holds up to 12 "plug-in modules". The "fixed modules" include some of the most common functions/building-blocks that are required in most experiments.
b)Thirteen Basic "plug-in modules". This BASIC MODULES SET includes ˇ@further fundamental building blocks required in many telecommunications and signal processing experiments.
c)2 groups of optional Advanced modules:
(i)The ADVANCED MODULE SET which includes more specialised building blocks, and,
(ii)The DSP MODULE SET.
8. What is the difference
between BASIC modules and ADVANCED modules?
The BASIC modules include the simplest, fundamental,
general purpose electronic building-blocks. eg. signal adder; signal multiplier;
filters; oscillators; phase shifters; etc.
The ADVANCED modules include more specialised or more specific electronic building-block functions. eg. PCM waveform encoders and decoders; bit error rate and signal to noise measuring functions; Delta modulation building-blocks; etc.
9. What equipment do I
need to use TIMS?
TIMS is intended as a complete, stand-alone
training system that typically only requires an oscilloscope and no other
test equipment.
The following is a complete list:
(i)TIMS system + optional modules;
(ii)Oscilloscope:2CH, 20MHz, conventional non-storage;
(iii) A personal computer with RS-232 port if the TIMS DSP modules are being used to develop programs.
10. How many experiments
can you do with TIMS? What kind of experiments can TIMS do?
Because TIMS models mathematical systems
using functional building-blocks, the number and type of experiments is
only limited by the modules (building-blocks) available and the user's
imagination (and understanding of the subject).
From this it follows that TIMS has an unlimited capability for telecommunications and signal processing experiments.
More specifically, we consider that with the FIXED and BASIC modules alone, over 50 experiments can be carried out.
The ADVANCED module set adds a further 25 new experiments.
Adding the DSP modules then expands the experiment base many times over.
11. What can I do if a
building-block (module) required for a particular experiment is not available?
The user has three options in adding completely
new types of experiments:
(i) Have a student or lecturer design and build a new module - for example, as a student project - using the TIMS PROJECT MODULE.
(ii)Have a student or lecturer write a DSP program to implement that function.
(iii)Ask Emona to consider developing such a module: we welcome suggestions.
TIMS has infinite expandability built-in !
12. How do you "model"
a telecommunications "channel"?
A "channel" is the path or medium along which
the modulated or coded message is transmitted. eg. radio waves, coaxial
cable, telephone line, etc).
In telecommunications, the characteristics of a "channel" must be known and measured, in order to ensure the message is correctly transferred from transmitter to receiver.
There are three important "channel" characteristics:
(i)signal amplitude attenuations and distortion.
(ii) signal phase delay and distortion
(iii)noise which is added to the signal.
TIMS uses a selection of filter plug-in modules to model the "channels" amplitude and phaseˇ@characteristics. "Channel" noise is modelled using a NOISE GENERATOR module.
13. How do I learn how
to put together experiments - where can I get some ideas?
Ideas for block diagrams are available from
many sources including:
(i) communications textbooks, magazines and research papers;
(ii) Emona's own "Ideas for Experiments" manuals;
(iii) the users own new ideas and theories;
(iv) the "Communication System Modelling with TIMS" text, by Tim Hooper.
14. Isn't TIMS just a
simple "demonstration" system?
TIMS is definitely not a "demonstration"
system.
A "demonstration" system is typically one
box, which only outputs demonstration waveforms eg: AM and DSB envelopes,
or TDM sampled signals, etc). The user has no real control over the method
of implementation of each experiment, other than a few gain controls.
TIMS is a true "modelling" system. No one module has an isolated function - modules are used together to build-up systems.
TIMS does not include, for example, an "AM modulator" module, or an "SSB demodulator" module. These functions are patched together using Adder Modules, Multiplier Modules, Signal Modules, and so on.
15. What is the MASTER
SIGNALS module?
MASTER SIGNALS is a "fixed module", which
provides the user with a set of synchronised carrier, sampling and baseband
signals.
16. Why is it important
that the MASTER SIGNALS outputs are synchronised?
Using synchronised signals in experiments
will allow the user to view ˇ@stable, "text book"- like waveforms on the
oscilloscope.
17. Why is the TIMS "carrier"
only 100kHz? Don't you know that in real telecommunications systems, carrier
frequencies can range from 1MHz to many tens of Giga Hertz?
TIMS is a mathematical, telecommunications
theory and signal processing modelling system.
TIMS models the mathematics. TIMS does not
consider high frequency circuit applications because this is a separate
and very specialised area of Electronics Circuit Theory.
For example, a student can model and take detailed measurements of a complete BPSK (binary phase shift keying) satellite link. The mathematical equations behind the theory of such a satellite link work both at 100kHz and at 10GHz. Only the circuits are different. The carrier frequency has ˇ@simply been scaled down to 100kHz.
18. Can TIMS DSP modules
be used with BASIC and ADVANCED modules?
Yes, of course. This is another of TIMS's
excellent feature: a DSP learning system that is integrated within the
TIMS environment. The TIMS environment provides the most flexible "test-bed"
for developing, debugging and testing DSP programs in telecommunications
and signal processing applications.
19. What is the difference
between the DSP Run Board (TIMS320 DSP-RB) and the DSP Development Board
(TIMS320 DSP-DB)?
The DSP-Run Board is intended for demonstrations
of real-time DSP functions, especially in introductory courses. The DSP
program can ONLY be installed in EPROMS.
The DSP-Development Board works exactly as the Run Board, plus it has an additional feature. Programs can be installed by EPROM or downloaded from a computer via an RS-232 interface into onboard RAM.
The DSP-Development Board is intended for program development and testing in more advanced and interactive courses.
20. Why does TIMS DSP
only use the Texas TMS320C10 DSP chip? Isn't it a waste of time showing
students a first generation DSP chip?
Even though TIMS DSP is not intended as a
high speed leading-edge DSP program development package, very advanced
projects such as complete Trellis Code Modulation (convolutional encoder/Viterbi
decoder) programs have been written and demonstrated by thesis students
using TIMS DSP modules and are available.
TIMS DSP's aim is to provide students with a low cost, "hands-on", teaching system that effectively introduces DSP concepts. There is no better "hands-on" DSP teaching system.
After carrying out experiments with the "electronic" modules, students are able to use the TIMS DSP modules to compare and contrast the "electronic" circuits' operation against the DSP implementation of the same functions. For example:
(i) compare active filters with DSP filters;
(ii)compare electronic phase shifters with DSP phase shifters;
(iii) compare quadrature sinewave generators with DSP sinewave generators;
(iv) experience the necessity of anti-aliasing and reconstruction filters;
(v)experience the limitations of instruction cycle to useable bandwidth; and so on.
Later, students can compare the operation of a group of modules with a DSP program implementing the same function.
By following the above examples, a student is gently introduced to the concepts and real-world applications of DSP. They learn DSP by actually doing and seeing DSP in real-time, not just on-screen computer simulations.
The student is not left thinking that DSP is some complex programming concept, because they have experienced the benefits and limitations of DSP.
Hence, TIMS teaches DSP concepts and not specific DSP instruction sets. The concepts and theories between implementing a DSP program on TIMS or on the latest DSP chip are the same: only speed (instruction cycle) and instruction set differ.
21. What is TIMS TRUNKS?
TIMS TRUNKS is an analog-channel bus that
allows a lab of TIMS units to be networked.
The lecturer is then able to send up to 3 signals (analog or digital) to every student's TIMS system. Any signal that can be generated on the TIMS unit can be sent down the TIMS TRUNKS bus.
TRUNKS installation is quick and easy:
(i)Select any standard TIMS. Plug the "Trunks Driver module" into the upper rack. This unit now becomes the "Master System".
(ii)Take the TIMS TRUNKS BUS ribbon cable, plug one end into the TRUNKS DRIVER module.
(iii)Along the bus there are 15-way connectors. Plug these connectors into the back of each student's TIMS.
(iv) The TRUNKSˇ@system is now ready to use. Any signal generated at the "Master System" can be input to the TRUNKS ˇ@DRIVER module, which will send that signal to every connected TIMS.
The transmitted signals are available to the student on their TRUNKS Panel (this is a standard part of the ˇ@FIXED set of modules). The student's TRUNKS Panel is labelled SIGNAL 1, SIGNAL 2 and SIGNAL 3: identifying each of the 3 signals on the TIMS Trunks Bus.
TIMS TRUNKS is a full differential system,
based on a standard ribbon cable bus. Each of the three channels has a
band width of typically 700kHz and a typical signal-to-noise ratio of 40dB.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
ˇ@