Date: April 7, 2014
To: Dr David Michelson
From:  Adebayo ADEGBOLA
Jeffrey CHU
Gregory LEE
Mustafa MUSSAYEV
Eric TUNG

Subject : ORBCOMM project update

This memo is an update for the week of March 30  – April 4, 2014.

Hardware

This week we were able to implement our sensors and also calibrate them accordingly. For our water level sensor, we implemented this using a R-2R ladder. As the height of the water increases the voltage increases. The flow rate sensor was implemented by sending the output  into one of the digital output on the Q4000 modem. A count function was implemented in the code, this helped to calculate the frequency of the flow. The output of the temperature sensor was multiplied by 100 in the code, this was done to get the temperature in celsius.

Software

We experienced some trouble this week when trying to forward e-mails to our ECE account. We received error mails saying “Disk quota exceeded”. We were able to resolve this by deleting some materials off  the z-drive in order to free some space. Sending values from our sensors through e-mails and displaying on PuTTY was achieved this week. The values sent through the email is saved as text on the z-drive. This is then opened in excel and saved as a CSV file. This file is then used in MATLAB to plot the graphs of all data received from the sensor.

Date: March 30th, 2014
To: Dr David Michelson
From:  Adebayo ADEGBOLA
Jeffrey CHU
Gregory LEE
Mustafa MUSSAYEV
Eric TUNG

Subject : OrbCOMM project update

This memo is an update for the week of March 24 – March 28, 2014.

For this week, we came up with different ideas for sensors and structure. Instead of salinity, we are going to be measuring the water level, water flow, and temperature. We also clarified whether or not a stationary object such as an oil rig was acceptable as opposed to something like a buoy. We chose to do this because these sensors fit more nicely with each other and allow us to tell a much better story. The scenario where these sensors could be applicable make much more sense than our previous sensors. We have managed to build and/or buy the sensors that we need for our project and have tested them to ensure that they work. What we still need to do hardware-wise is to build the actual oil rig itself.

In terms of software, we were having difficulties getting the emails to forward properly to the proper folders with the value of one of the input channels on the modem. However, there is a problem in that it will forward properly for the first couple of emails but fail to forward all the emails after that. We have yet to find out why this problem occurs. What we need to do now is to ensure that all the data that we measure is sent through email successfully, not just a single value. In addition, we need to add a function that can help measure the flow rate of the water.

Date: March 23rd ,2014

To: Dr David Michelson

From:  Adebayo ADEGBOLA

          Jeffrey CHU

          Gregory LEE

          Mustafa MUSSAYEV

           Eric TUNG

Subject : OrbCOMM project update

This memo is an update for the week of March 17 – March 21, 2014.

This week, our team decided on the features that we want to have in our project, such as salinity, viscosity and temperature meters. The hardware parts that are required for building were determined and a team member was appointed for buying components.

In the lab on the wednesday, we set up a timer and changed the IAR program so that is shows a particular message on PUTTY periodically. Also the team tried to show two different messages at the same time, however later we found out that it is not possible.

In the lab on friday, we created a folder to collect all the mail from the satellite with. The mail which was delivered to our gmail account at first was now filtered and redirected by gmail to our ece email. We added some lines in our code so that the mail shows specific subject line, which was “L2D2 testing” for us. In addition, we learned to use the Batch scripting method.

Date: March 14th ,2014

To: Dr David Michelson

From: Adebayo ADEGBOLA

        Jeffrey CHU, Team Leader

        Gregory LEE

        Mustafa MUSSAYEV

         Eric TUNG

Subject : OrbCOMM project update

This memo is an update for the week of March 10 – March 14, 2014.

This week, we had a tutorial on reading values and flash file saving in the lab. In the lecture, we reflected on how our first project went. there was no group meeting as we did not know enough to do anything on project yet. During the tutorial, we learned how to adjust the Q4000 to read from different ports by altering the code. We created a voltage divider with resistors found in the lab and fed it into port 0 of the modem, then we altered the original code to read from that port. It was successful and were able to detect changes in the values displayed on the computer. However, we did not look for a way to change the conversion factor.

In the Friday lab, we got the Q4000 to send an email to our group email that contained a message inside. The message said “team l2d2 was the best”. Our Next goal is to come up ideas for our project,and then begin working on it as soon as possible. Since we do not have much time left, we must work quickly and efficiently without much room for error in order to be successful on this project.

MEMORANDUM

TEAM L2D2

Adebayo ADEGBOLA

Jeffrey CHU

Gregory LEE

Mustafa MUSSAYEV

Eric TUNG TEAM LEADER

Week 1(March.3 – March.7) – Spectrum Analyzer Demo and Starting Project 2

During this week we had:

• lecture on Monday on team meeting strategies

• spectrum analyzer demo on Wednesday and lab tutorial on Friday

Wednesday

This week was our demo week and on Monday we still had quite a bit of troubleshooting to complete. Our peak detector suddenly broke down and we rebuilt the same circuit many times but it never worked. Our solution was to try to build a different circuit. Although this plan worked, our output from the peak detector was not as accurate due to larger fluctuation. Even after our calibrations, the dBm is sometimes accurate and sometimes inaccurate. We decided to stick with this because we did not have enough time to make more adjustments. Overall, the demo was very successful and we were very happy with our results.

Friday

We started our new project, the Orbcomm project, during this lab session. Being quite different from the Spectrum Analyzer project, we realized it was something we would definitely have to learn more about and get used to. We spent almost one third of the lab session being taught the basics of the project such as how to use Putty and roughly how we are supposed to complete it. For this lab session, we were given the task of editing a file of C code to send an email to our group email that we created this session as well. While it sounds quite simple, it proved to be more difficult than we had originally thought. We did manage to send one or two emails but could not get an email to send consistently. By the end of the lab session, we had three emails sent to our group email.

Date: March 2, 2014

To: Dr David Michelson

From: Jeffrey CHU – Team Leader

Adebayo ADEGBOLA

Gregory LEE

Mustafa MUSSAYEV

Eric TUNG

Subject : Spectrum Analyzer Project Update.

This memorandum is an update for the week of February 24 – march 2, 2014.

Hardware

We faced issues with the common emitter transistor amplifier as the AC input voltage was not amplifying. But after playing with some values, we were able to get it working with 2 NPN 3904 transistors. The peak detector also gave us some issues which we managed to fix Friday by messing around with the peak detector part values. At the end of Friday, we managed to solve most of the hardware issues, put everything together and get it working very well with our software with frequencies between 51 to 54 Mhz. We could not get a bench on Saturday because the lab was full, and people hogged the benches for a very very very long time >: E .  the project on the oher hand, was going well, until Sunday where everything suddenly stopped working for some unknown reason.

Software

The software is working well, as we were able to implement a log amplifier, and a video filter. We also adjusted the frequencies and offset of our ramp generator so that it could detect 50 Mhz.

We are currently troubleshooting our hardware to see what the issue is, and to take the appropriate measures to fix it, and get it working before the date of our demo.

ECE 380 Design Studio III

Memorandum 4

TEAM L2D2

Date: February 16,2014

To: Dr David Michelson

From: Adebayo ADEGBOLA, Team Leader

        Jeffrey CHU

        Gregory LEE

        Mustafa MUSSAYEV

         Eric TUNG

Subject : Spectrum Analyzer Project Update.

This memorandum is an update for the week of February 10 – February 14, 2014.

We had our weekly team meeting on Friday 14, where we talked about the general progress of the project. This discussion was based on the hardware and software portion of the project.

Hardware

The issues with the resolution bandwidth filter were fixed. A bandpass filter with a bandwidth of 950-1000 Hz was designed and was checked using the tracking function on the hp spectrum analyzer. There are still issues with peak detector not being able to measure peak effectively at low power(-30dBm and -60dBm). We are currently looking into using a basic full wave, balanced, diode RF detector.

Software

The myDaq has been confirmed to trace DC voltage going into it. A log function has also been created to help convert this DC voltage to power. Minor adjustments need to be made to meet requirements for our log amplifier.  The display of the spectrum has also been tested with DC voltage on the y axis, conversion needs to done to change this power.

The next step of this project is to gradually put all individual components together to see how they respond.

MEMORANDUM

TEAM L2D2

Adebayo ADEGBOLA

Jeffrey CHU

Gregory LEE

Mustafa MUSSAYEV

Eric TUNG

Week 5(Feb.3 – Feb.7) – Experimentation and Troubleshooting

During this week we had:

• lecture on Monday about the formal report

• two labs on Wednesday and Friday

Wednesday

The peak detector that we created works for 10 dBm which was not low enough to meet the -60 to -20 dBm project specifications. With the RF amplifier, we managed to get it working to about -30 dBm, but that was still not low enough. Our current solutions to the amplifying problems are either to buy high frequency OP amps or use high power RF amplifiers. As for the myDAQ part of the project, we were still figuring out how to use the ramp generator correctly with the VCO.

Friday

After the team meeting on Friday, we had a better understanding of what to achieve for the myDAQ part of the project. We wanted the output of the mixer to be 10MHz and since the project specifications for the RF Input is 50-54MHz, we use this formula:

Mixer output = | f(lo) – f(rf) |

This meant that the local oscillator had to have a frequency of roughly 60-64MHz to get a 10MHz output. To do that with the VCO, our ramp generator had to supply a voltage between 4 and 6 volts in order to generate 60-64MHz (this information was taken from the ZX95-100 Frequency and Tuning Sensitivity graph). To verify that we have done this process correctly, we tested the VCO with the spectrum analyzer to see if there were peaks at the right spots. After checking with the spectrum analyzer, we had peaks coming out of the VCO at the correct frequencies. For the hardware portion, we’ve created a band pass filter but it has not yet met our expectations because it was not rejecting frequencies higher than 10MHz.

TEAM L2D2

Adebayo ADEGBOLA

Jeffrey CHU

Gregory LEE

Mustafa MUSSAYEV

Eric TUNG

Week 4 (Jan.27 – Jan 31) – FINAL TUTORIAL AND PROJECT COMMENCEMENT

During this week we had:

·         lecture on Monday

·         two labs on Wednesday and Friday

Wednesday

The lab on this day consisted of the final tutorial session for the spectrum analyzer. While previous tutorials and their activities taught us how to use a spectrum analyzer, this tutorial showed us the basics of how a spectrum analyzer actually works. Activities included splitting the group into a software development team and the RF front end team, building a peak detector, and connecting the ESG generator into the HP8920A RF Communication Test Set. In addition, we learned about the frequency modulation that occurs in a spectrum analyzer. These activities are centered around the hardware side as the software side involves learning how myDAQ works and following the instructions given on their website and manual. As for the hardware side, we mainly spent this lab session learning about each component needed for this project, specifically the peak detector and resolution bandwidth filter. Using the crystals given in our lab kit, we plan to construct a filter that gives 2.7kHz-3kHz BW. For the peak detector, we learned that it will receive a 10MHz signal from the BW filter. This means our RC or т value is inversely related to w (omega). Since we know that w=2pi*f, we were able to choose the resistor and capacitor values we want to get the frequency we need.

Friday

For the myDAQ, we managed to produce a continuous triangle wave after some trial and error so our ramp generator portion is complete. As for the hardware, we went into more detail on each component, especially the Resolution BW Filter. We came up with a circuit that will allow us to configure the crystals in such a way so that our desired BW can be achieved. We also had a team meeting as to what we planned to do over the weekend as well as next week.

MEMORANDUM

TEAM L2D2

Adebayo ADEGBOLA

Jeffrey CHU

Gregory LEE

Mustafa MUSSAYEV

Eric TUNG

Week 3 (Jan.19 – Jan 26) – FOCUSING ON CONCEPTS AND TOOLS

During this week we had:

• lecture on Monday
• two labs on Wednesday and Friday

Wednesday

During this lab time basics of spectrum analyzer were introduced to teams: what is a spectrum analyzer, how it works and how to use one of the spectrum analyzers in the lab. In addition, some project specifications were introduced. Lab activities helped us to use spectrum analyzers in the lab along with signal generators and oscilloscope. We utilized cables and connectors (BNC, SMA, N connector, TEE, mixer) to connect these tools together. We observed how the change in RBW (Resolution Band Width) can affect sweeping time, noise floor and frequency resolution. Using TEE connector we connected oscilloscope and signal generator to the SA and observed output from square and triangular waveforms. The output did not differ since it shows the power in dB in a signal, but not its shape. Mixing signals from two signal generators helped us to see how mixing happens according to the following formulas:

f(lo) = f(if)+f(rf)

f(lo) = |f(if) – f(rf)|, lo – local oscillator, if – intermediate frequency

Friday

During the first lab activity we learned how to create a VCO (Voltage Controlled Oscillator) using ZX95-100. Using this device one can sweep using DC supply or using ramp and sine wave generators. Also ZFL-500 was using to amplify RF amplifier. We could observe the limits of the amplifier. In the following lab activities we learned how to set up a tracking generator and use two different band pass filters (BBP=70+ and BBP-10.7+).  In the last lab activity we put together VCO, that worked as a LO, a mixer and spectrum analyzer. In addition we used BBPs to limit the frequencies.