From picone at ece.msstate.edu Wed Jan 7 17:13:56 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Wed Jan 7 17:14:56 2009 Subject: [ece3163] ECE 3163: Welcome to Signals and Systems Message-ID: <49653734.2070500@ece.msstate.edu> (I am resending this message for those who did not receive it.) One more thing: If you don't like this semester's lectures, you can always revert to last semester's lecture at: http://www.isip.piconepress.com/publications/courses/ece_3163/lectures/2008_fall/ -Joe ==================================================================== Each of you is enrolled in the Signals and Systems course that I will teach this spring. I am very excited about teaching this course since I consider this course one of the cornerstones in your undergraduate education. The course web site is located here: http://www.isip.piconepress.com/publications/courses/ece_3163/ The couse web site is ready for your review. Pay special attention to the course syllabus. Please read it carefully so we don't have to spend time on this in our first class. I'll be happy to answer any questions via email. Also, please try to read Sections 1.1 and 1.2 for Monday's class and to review the lecture notes. Reading ahead will be an important way to prepare yourself for each lecture. You will note that audio is available along with the lecture notes. This is so you can put yourself to sleep each night to the sweet sounds of a Signals and Systems lecture ;) It also makes for great entertainment while you are exercising. These lectures are recordings of last semester's lectures. I will update the audio archives daily as we progress through the semester. To further my preparations for the course, I'd like you to tell me a little more about yourselves. I have reviewed your academic records online, but that doesn't tell me the entire story. I am specifically interested in knowing what aspects of your undergraduate education have you enjoyed, what fields you are considering to pursue upon graduation, and whether you consider yourself strong in theory, practice or both. As you have probably heard, this course requires a good grasp of Calculus and other related concepts in engineering mathematics. Next, I'd like to know something about your future employment plans. What type of job do you plan to pursue? research? development? design? support? etc. What types of courses are you planning on taking to prepare you for such a job? Finally, I'd like to know more about your relevant background in software. Are you familiar with MATLAB (the answer should be yes)? What other computer languages do you know? What significant experiences have you had involving computer modeling and simulation? I hope we can push the envelope a bit this semester in this course. This field is moving very quickly. There have been a lot of good developments in the past 5 to 10 years. A background in this material is essential if you want to get a decent job in a related area since most employers now expect engineers to be capable to modeling and simulating the systems that they develop. I think if we all work hard this semester we can accomplish a great deal. Let me know if you have any additional questions. Best regards, Joe Picone From picone at ece.msstate.edu Wed Jan 7 22:52:49 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Wed Jan 7 22:53:46 2009 Subject: [ece3163] lecture no. 1 Message-ID: <496586A1.3050407@ece.msstate.edu> Today we covered a few important mathematical details that you need to be very comfortable with. First, there is the complex function: exp(st) = exp(sigma*t) exp(j*omega*t) Second, we talked about the fact that the second term, exp(omega*t), is a vector of magnitude 1 and angle of omega*t radians. It has real and imaginary parts: Re{exp(j*omega*t)) = cos(omega*t) Im(exp(j*omega*t)) = sin(omega*t) Third, we talked about symmetry properties: even function: x(t) = x(-t) odd function: x(t) = -x(-t) Traditionally, students have had trouble with these concepts. I would encourage you to meet with Tao if you need further explanations of these concepts. -Joe From picone at ece.msstate.edu Thu Jan 8 22:45:08 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Fri Jan 9 08:33:42 2009 Subject: [ece3163] password for homework Message-ID: <4966D654.9010607@ece.msstate.edu> The homework solutions are located at: http://www.isip.piconepress.com/publications/courses/ece_3163/homework/current/ The username/password are both "ece_3163". -Joe From picone at ece.msstate.edu Sat Jan 10 08:24:54 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Sat Jan 10 08:25:21 2009 Subject: [ece3163] Friday's lecture Message-ID: <4968AFB6.3010000@ece.msstate.edu> The audio for each class will be posted shortly after the class. The audio from Friday's lecture is now available in the lecture notes directory. Since we had a technical problem at the beginning of class that disrupted the flow of the lecture, you might also want to listen to last semester's lecture at: http://www.isip.piconepress.com/publications/courses/ece_3163/lectures/2008_fall/lecture_02.mp3 I also made a few updates to the notes based on feedback from the lecture (such as the figure denoting the impulse function). Two key points from Friday's lecture were the definition of an impulse function, delta(t), and the principle of time-shifting, x(t+t_1) or x(t-t_1), -Joe From picone at ece.msstate.edu Sat Jan 10 13:44:12 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Sat Jan 10 13:44:51 2009 Subject: [ece3163] homework In-Reply-To: <1231616003.4968f80312bf9@webmail.msstate.edu> References: <1231616003.4968f80312bf9@webmail.msstate.edu> Message-ID: <4968FA8C.1080006@ece.msstate.edu> > I was able to access the homework directory using the username/password > provided. I was unable to open hw 1 (403 error)...and I was just wondering has > it been assigned and will you be unlocking them as you assign them? > I fixed a permission problem with the files. Sorry about that. The homework assignments are listed at the end of the syllabus. They are "assigned" as we cover the corresponding material in class. Since homework is not collected, you have some flexibility in when you work it. However, Tao is going to move very quickly in the recitation sections, so you will need to keep up. We are going to cover roughly a chapter a week in this course, so just about every week you should be able to do some new homework problems. Let me know if you have additional questions. -Joe From picone at ece.msstate.edu Mon Jan 12 13:31:16 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Mon Jan 12 13:31:47 2009 Subject: [ece3163] today's lecture Message-ID: <496B9A84.6060404@ece.msstate.edu> Today we covered three important properties of a system: - causality - linearity - time-invariance A consequence of these is that the output of a linear, time-invariant system to a periodic input is also a periodic signal (at the same period as the input). The amplitude of the output can change, especially if the system behaves as some sort of filter, but the nature of the output stays the same -- a periodic signal. We didn't have time to cover slide 10 in the lecture notes. Tao will cover this in the recitation section. It is an example of how we can use linearity and time-invariance to compute an output. Tao will also explain the examples in slides 6 and 8 in more detail. Finally, I fixed a permission problem in the exam directory. See you on Wednesday. -Joe From picone at ece.msstate.edu Mon Jan 12 13:48:47 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Mon Jan 12 13:49:18 2009 Subject: [ece3163] Re: MATLAB In-Reply-To: <59a103e30901121145i38549104scbfe7c6727857bfd@mail.gmail.com> References: <59a103e30901121145i38549104scbfe7c6727857bfd@mail.gmail.com> Message-ID: <496B9E9F.606@ece.msstate.edu> > Is there a reason that you have chosen to use the MATLAB version R2007a > instead of version R2008b? I am just curious because if it makes no > difference I would rather the latest software. > We will use whatever is the latest installed version. I am using 2008a on my laptop. The university can provide you with this version if you don't have it. -Joe From picone at ece.msstate.edu Mon Jan 12 14:10:32 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Mon Jan 12 14:10:58 2009 Subject: [ece3163] recitation section In-Reply-To: <200901122000.n0CK0PJb026455@catalpa.its.msstate.edu> References: <200901122000.n0CK0PJb026455@catalpa.its.msstate.edu> Message-ID: <496BA3B8.20601@ece.msstate.edu> > Will there be any sort of notes available online from the recitation > sessions for those of us who cannot attend because of labs? > Good question. Tao will record the audio and post any Matlab code. As far as other forms of notes, we will have to think about that. We don't have a convenient way of capturing the handwritten notes from the whiteboards. -Joe From picone at ece.msstate.edu Mon Jan 12 21:57:01 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Mon Jan 12 21:57:56 2009 Subject: [ece3163] This Is Spinal Tap -- "It is one louder." Message-ID: <496C110D.8030205@ece.msstate.edu> In class we were talking about the nonlinear nature of volume controls. Well, here is one of the most famous movie moments on this topic: http://www.youtube.com/watch?v=akaD9v460yI In it, the band, known in their early years for being the loudest rock band in the world, explains that their secret to success is that their amplifiers go up to 11, while others only go up to 10, so therefore "It's one louder." If you want to see a very good mockumentary on an aging rock band, you must see this movie: http://www.imdb.com/title/tt0088258/ - "This Is Spinal Tap" There is another famous sequence about the importance of engineering requirements in this movie. The band orders an elaborate stage prop to be constructed for the big conclusion to their new hit song. Unfortunately, there was a miscommunication about the dimensions of the object because the "specs" were drawn on a napkin. Well, you can imagine what happens. On the topic of linearity, I have this note from last semester: "In the Thursday night study session, we were talking about how products are designed to operate over a range that is usually only a fraction of their full scale. Amplifiers, for example, are typically linear over only about 50% or 75% of their operating range. The speakers in a car audio system will most likely fail quickly if the radio is played continuously at full volume. Operating equipment at the extremes, such as full scale, often leads to quick burnout of the device, because devices are normally not designed to operate at full scale continuously. The full scale setting is more so they can advertise a certain operating range that is greater than their competitor (e.g., 200 Watts of power) when in fact it is probably more optimal to operate that device at half its rating (e.g., 100 Watts). This is called "specmanship" (or specification engineering)." The YouTube clip is a famous take-off on this concept. Hope you enjoy it. -Joe From picone at ece.msstate.edu Tue Jan 13 09:33:17 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Tue Jan 13 09:34:06 2009 Subject: [Fwd: Re: [ece3163-01] [ece3163] This Is Spinal Tap -- "It is one louder."] Message-ID: <496CB43D.7010002@ece.msstate.edu> Steven Howell added some nice observations about amplifiers and nonlinearities. I'll send out more information about nonlinear amplifiers in a couple of lectures to further drive home the point about periodic signals and linear time-invariant systems. -Joe -------- Original Message -------- Subject: Re: [ece3163-01] [ece3163] This Is Spinal Tap -- "It is one louder." Date: Tue, 13 Jan 2009 04:58:55 +0000 (GMT) From: Steven Howell To: joseph.picone@gmail.com References: <496C110D.8030205@ece.msstate.edu> I have this movie on DVD. Is there any chance that the class could use a room to watch it sometime? One of the more ironic things about the movie is that it is barely a satire of what rock bands where like in the 80s. Just about everything in that movie is based on true events. Rock musicians can be some of the silliest people on the planet. > "In the Thursday night study session, we were talking about how > productsare designed to operate over a range that is usually only a > fraction of > their full scale. Amplifiers, for example, are typically linear over > only about 50% or 75% of their operating range. The speakers in a car > audio system will most likely fail quickly if the radio is played > continuously at full volume. one thing interesting about this in regards to rock music is that the distortion of rock music comes from driving an amplifier into that top operating range. Even though the technology is old, engineers have yet to fully document the science behind the sound of rock. Because of this, there have yet to be accurate and complete simulation software made for designing "rock" amplifiers. Most of the software that simulates guitar amplifiers actually simulates the sound waves produced by the cab within a room, and not the circuit of the amplifier. Steven Howell ----- Original Message ----- From: Joseph Picone Date: Monday, January 12, 2009 9:59 pm Subject: [ece3163-01] [ece3163] This Is Spinal Tap -- "It is one louder." To: ece3163@ece.msstate.edu > In class we were talking about the nonlinear nature of volume > controls. > Well, here is one of the most famous movie moments on this topic: > > http://www.youtube.com/watch?v=akaD9v460yI > > In it, the band, known in their early years for being the loudest rock > band in the world, explains that their secret to success is that their > amplifiers go up to 11, while others only go up to 10, so therefore > "It's one louder." > > If you want to see a very good mockumentary on an aging rock band, you > must see this movie: > > http://www.imdb.com/title/tt0088258/ - "This Is Spinal Tap" > > There is another famous sequence about the importance of > engineering > requirements in this movie. The band orders an elaborate stage prop > to > be constructed for the big conclusion to their new hit song. > Unfortunately, there was a miscommunication about the dimensions of > the > object because the "specs" were drawn on a napkin. Well, you can > imagine > what happens. > > On the topic of linearity, I have this note from last semester: > > "In the Thursday night study session, we were talking about how > productsare designed to operate over a range that is usually only a > fraction of > their full scale. Amplifiers, for example, are typically linear over > only about 50% or 75% of their operating range. The speakers in a car > audio system will most likely fail quickly if the radio is played > continuously at full volume. > > Operating equipment at the extremes, such as full scale, often > leads to > quick burnout of the device, because devices are normally not designed > to operate at full scale continuously. The full scale setting is > more so > they can advertise a certain operating range that is greater than > theircompetitor (e.g., 200 Watts of power) when in fact it is > probably more > optimal to operate that device at half its rating (e.g., 100 Watts). > This is called "specmanship" (or specification engineering)." > > The YouTube clip is a famous take-off on this concept. > > Hope you enjoy it. > > -Joe > > _______________________________________________ > ece3163 mailing list > ece3163@ece.msstate.edu > http://www.ece.msstate.edu/mailman/listinfo/ece3163 > _______________________________________________ > ece3163-01 mailing list > ece3163-01@ece.msstate.edu > http://www.ece.msstate.edu/mailman/listinfo/ece3163-01 > From picone at ece.msstate.edu Thu Jan 15 00:19:28 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Thu Jan 15 00:20:32 2009 Subject: [ece3163] recitation sections Message-ID: <496ED570.20407@ece.msstate.edu> I have uploaded Tao's notes and audio from the first recitation section to this location: http://www.isip.piconepress.com/publications/courses/ece_3163/recitations/current/ This is also linked from the main page of the course web site. Tao will be scheduling an additional recitation section on Thursday at which he will review this material for those of you who can't make the Tuesday section. An announcement with the details will follow shortly. -Joe From picone at ece.msstate.edu Thu Jan 15 07:32:37 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Thu Jan 15 07:33:45 2009 Subject: [ece3163] MATLAB examples from lecture 04 Message-ID: <496F3AF5.4030708@ece.msstate.edu> MATLAB code to compute some of the statistical measures discussed in lecture 04 can be found at: http://www.isip.piconepress.com/publications/courses/ece_3163/matlab/2009_spring/statistics/ An additional set of examples can be found in the parent directory: http://www.isip.piconepress.com/publications/courses/ece_3163/matlab/ There are lots of resources on the web for learning to program in MATLAB as well as many repositories of MATLAB examples. -Joe From tm334 at ece.msstate.edu Thu Jan 15 21:16:04 2009 From: tm334 at ece.msstate.edu (Tao Ma) Date: Thu Jan 15 21:16:08 2009 Subject: [ece3163] Additional Recitation on Thursday In-Reply-To: <496ED570.20407@ece.msstate.edu> References: <496ED570.20407@ece.msstate.edu> Message-ID: <496FFBF4.7000207@ece.msstate.edu> From next week, we will add another recitation lecture on Thursday at same time (7-9pm) in same place (Simral 129). The content will be exactly the same as Tuesday's. Again, please do your homework before coming to the lecture. And you will be asked to solve problems on white board. -Tao From tm334 at ece.msstate.edu Thu Jan 15 21:32:54 2009 From: tm334 at ece.msstate.edu (Tao Ma) Date: Thu Jan 15 21:32:59 2009 Subject: [ece3163] TA Office Hours Change In-Reply-To: <496FFBF4.7000207@ece.msstate.edu> References: <496ED570.20407@ece.msstate.edu> <496FFBF4.7000207@ece.msstate.edu> Message-ID: <496FFFE6.4010708@ece.msstate.edu> Office hours has changed to Tuesday Thursday 9-10pm to fit the recitation schedule. My seat is behind a wall (you can't see me through outside), so please knock the door or give me a call when you come. Thanks, -Tao From picone at ece.msstate.edu Fri Jan 16 12:38:05 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Fri Jan 16 12:39:06 2009 Subject: [ece3163] discrete-time convolution Message-ID: <4970D40D.5030205@ece.msstate.edu> In today's lecture, we demonstrated the use of convolution to compute the output of a linear, time-invariant system. We introduced the convolution summation and showed examples of the computation both analytically and graphically. At this URL: http://www.isip.piconepress.com/projects/speech/software/demonstrations/applets/util/convolution/current/index.html you will find a Java applet that allows you to solve homework problems using an animated visualization of convolution. Give it a try. Tao will also lead you through some homework problems in the recitation section next week. Have a nice (extended) weekend. -Joe From picone at ece.msstate.edu Mon Jan 26 13:31:44 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Mon Jan 26 13:32:16 2009 Subject: [ece3163] loudness and nonlinearities Message-ID: <497E0FA0.2070107@ece.msstate.edu> Steven Howell pointed me to this YouTube video. It is very nicely done: http://www.youtube.com/watch?v=3Gmex_4hreQ We have an interesting class this semester. I am enjoying the discussions on music and other things. Let's keep it going. -Joe From picone at ece.msstate.edu Mon Jan 26 20:43:16 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Mon Jan 26 20:44:00 2009 Subject: [ece3163] loudness wars - part II Message-ID: <497E74C4.3080502@ece.msstate.edu> Steven also passed along a URL to a video on the topic of loudness: http://www.youtube.com/watch?v=DRyIACDCc1I There has been a lot of discussion about the compromises in quality on the CD to improve the impact of the music when heard over the radio. As we were explaining in class, sometimes nonlinear distortion of a signal can be preferred to the pristine digitally sampled version. In a month or so you will understand this from a mathematical point of view. -Joe From picone at ece.msstate.edu Sat Jan 31 08:37:38 2009 From: picone at ece.msstate.edu (Joseph Picone) Date: Sat Jan 31 08:38:15 2009 Subject: [ece3163] Heisenberg Uncertainty Principle and Teleportation Message-ID: <49846232.3070205@ece.msstate.edu> A question came up in class about the Heisenberg uncertainty principle. Here are some pointers to this topic: http://en.wikipedia.org/wiki/Uncertainty_principle http://www.aip.org/history/heisenberg/p08.htm The relationship between time and frequency can be viewed in terms of this principle. Also, here is an interesting article on a related concept, teleportation: http://www.time.com/time/health/article/0,8599,1874760,00.html Enjoy! -Joe