To: David G Michelson

From: EECE 380 Team L2D8

Date: April 6 2014

Subject: Project 2 Weekly Memo 9

Dear Professor Michelson,

This memorandum outlines the latest progress of the team for the week.

Achievements from Last Week

Our team assembled the crystal filter, amplifier and the peak detector altogether and tested the hardware as a whole. We also modified the LabVIEW software to run the local oscillator and display the signal spectrum using the waveform graph display. MyDAQ is connected to the hardware and it has two analog inputs coming in from the hardware. We run the program, observed the signal and debug the hardware all in the same time. Various frequencies were used and tested to ensure optimal performance of the hardware. In order to display the signal better in LabVIEW, we modified the offsets, signal run frequency and the number of samples run per second. We also tried to convert the signal to a log scale and convert the x-axis to frequency domain. To improve the peak display in LabVIEW, we monitor the discharge rate of the capacitor in the peak detector circuit.

Progress for this week

Both the hardware and software parts are assembled altogether and our team debug any possible problems may arise during the testing phase. We realized the signal spectrum was not displayed properly in LabVIEW, therefore we changed the offset and the scale of the axis. Different input frequencies and amplitudes were used to test the hardware, and we observed the displayed results in real time. We also ensure that the capacitors are discharged in a desirable time in order to improve the overall performance. After the final testing phase where the results are correctly displayed, we are ready for our project’s demonstration.

Problems and Improvements

Our team learned a lot throughout this project. We realized that sometimes the signal spectrum was not displayed correctly. This is because the Schottky diode was not connected properly in the circuit, which caused the capacitor to not discharge properly to produce a peak for the signal. The amplifier depends heavily on the values of the resistor we used. We biased the circuit and tested with different values of resistors using Multisim and Circuit Maker. We also observed the amplified voltage using the oscilloscope. In order to improve performance, we learned to calculate the right values of resistors to be used for the hardware.

MEMORANDUM

To : Dave Michelson

From : EECE 380 Team L2D8

Date : 31 March 2014

Subject : Project 2 Weekly Memo 8

INTRODUCTION

This memo outlines the progress made during the last week before the project.

PROGRESS

Hardware

With the new capacitor stocks, we finished adjusting the bandwidth of our crystal filters, ~1kHz and ~3kHz approximately.

When the RF signal is passed through the crystal ladder, there was approximately a 23 dBm loss. Therefore, we chose to build a cascode which amplifies the signal by approximately 20 dBm to compensate for the loss. The cascode is chosen due to its ability to isolate both the input and output stages, high gain and slightly wider bandwidth compared to the standard common emitter amplfier.

We also built a simple peak detector which has a stable output without any ripple. This allows for a clean input into myDAQ so that the readings are more accurate.

Software

We managed to display the xy graph in Labview as well reading the input voltage. There is also a cursor on the display that displays the values.

GOALS  FOR NEXT WEEK

1. Test the whole circuit with the RF Amplifier, Mixer, VCO, Attenuator, switch and software

2. Start designing the PCB Board

3. Include the frequency modulation Beta into Labview.

To: David G Michelson

From: EECE 380 Team L2D8

Date: March 23 2014

Subject: Project 2 Weekly Memo 7

This memo outlines the progress made this week as well as goals for next week.

Progress

The group has identify the key parts of the project and assigned jobs to each group members.

2 members are working on the software while the other 3 are working on the hardware.

Hardware

We have built the peak detector as well as the two resolution bandwidth filters. Both resolution bandwidth filters has a centre frequency of 8Mhz. However, the bandwidth of the bandwidth filter is not yet adjusted because the capacitor stock ran out. We would continue with the adjustment in the following week after obtaining the appropriate capacitor values.

Besides that, we built an amplifier for the ramp generator because the maximum voltage output from the myDAQ is not enough to sweep through our local oscillator range from 78 Mhz to 98 Mhz.

Software

There has been no update to the software portion this week. All members were focusing on the hardware part of the project for now.

Goals for Next Week

1. Start building the transistor amplifiers

2. Assemble everything together

3. Test the circuit out with the software.

To: David G Michelson

From: EECE 380 Team L2D8

Date: March 16 2014

Subject: Project 2 Weekly Memo 6

This memo summarizes the progress from the first tutorial to the thrid tutorial. In time span, it includes the material from March 7th to March 14th.

What we learned so far

In the first tutorial, we familiarized ourselves with the spectrum analyzer and the signal generator. We also learned to set up NI myDAQ, data acquisition device. The first tutorial was pretty preliminary. In the second tutorial, we were asked to test different components. We found out that the gains of components are as follows:
Frequency Mixer
-7 dB
RF Amplifier
22 dB
Band Pass Filter
-0.7 dB
Attenuator
-10 dB
In theory, the signal right after the RBW filter will have a very small gain of 4.3 dB. We connected everything with a 0 dBm 50 MHz signal and the peak value was observed to be around 5 dBm which is very close to the theoretical value. Particularly, we noticed that the output signal of VCO is 0 dBm instead of typical 10 dBm on the datasheet, and the final experiment also proved us right. In the third tutorial, we spent most of our time finishing up the second tutorial, but it clearly showed us what we need to do next week.

Problems Identified

The problem is that the local oscillator can only produce signals between 40MHz and 80MHz due to the voltage output limit of myDAQ. The most likely solution is to build an amplifier to amplify the voltage of ramp signal to the desired range. The other problem is that the high frequency band pass filter we have right now is centered at 10.7 MHz. To get 8 MHz center frequency, we need to find some solutions.

Work Ahead

Try thinking about solution for measuring modulation index or frequency deviation.
Try searching the solutions to adjust the center frequency of band pass filter to 8MHz.
Hardware wise: Two sets of crystal filters are needed. Two sets of high frequency peak detectors are needed. One transistor amplifier with gain around 1.4 is needed.
Software wise: In the LABVIEW, use block diagram to plot the data acquired from ramp generator and peak detector. Try to add the switch for the crystal filter.

To: David G Michelson

From: EECE 380 Team L2D8

Date: march 2 2014

Subject: Project 1 Weekly Memo 5

Dear Professor Michelson,

This memorandum outlines the latest progress of the team for the week. The progress is being discussed into three main topics below.

Achievements from Last Week

        From last week, bash scripting, email subject line and header, sending ADC voltage values to our email parts are successfully done. Also, after discussions we came out with several ways to calculate the wind speed. The ideas that we came out with are to use Hall Effect sensor, rotationary encoder and optical sensor. After the discussions, we have ordered all the components.

Progress for this week

       After receiving all the components we have tested them to come out with the best way to measure the wind speed. The fist, the optical sensor provides poor reaction time. Thus, we conclude that optical sensor will not be able to react to our hardware part which is pretty fast. Secondly, we figured out that we have to overcome too much friction force to spin the rotationary encoder. Therefore, we conclude that the encoder is not a appropriate way. Finally, we decide to use the hall effect sensor which provide us quite perfect reaction time and voltage graph.

Goals for Next Week

All the components are ready and demo-date is almost there thus, we will have to finish all the work. Also, since mechanical part of the project is not yet completed, we have to focus on building a wind-speed detector and temperature sensor.

To: David G Michelson

From: EECE 380 Team L2D8

Date: February 14 2014

Subject: Project 1 Weekly Memo 4

Dear Professor Michelson,

This memorandum outlines the latest progress of the team for the week. The progress is being discussed into three main topics below.

Achievements from Last Week

Over the last week, our team organized a meeting to discuss ideas in designing and building circuits for the hardware part of the project. We researched on different types of motors and sensors in order to obtain the suitable ones to be used in our design. We decided some mandatory components and drew circuits for our design.  On last Friday we have learned how to use PUTTY to run scripts, create email filter and check forwarding in the email. We also continued working on the code using the computer and the modem in the lab.

Progress for This Week

During this week, we have successfully completed bash scripting, email subject line and header and had the ADC voltage values sent to our email. The ADC circuit we built last week is used to measure the voltage values. The voltage value changes with different voltage input values and the range is set to be from zero volts to 3.5 volts. We also started building the hardware part of the project after our team discussed and choose the best design. Currently we are continuing working on the FFS and GSM and hopefully improve the time delay between sending signals to the satellite and receiving the emails in return. We also use Orbcomm commands and currently working on to combine FFS and email contents by modifying the code.

Goals for Next Week

As reading week commences, our team decided to meet in the lab to continue working on both the hardware and software parts of the project. We are still waiting for our ordered parts to arrive and hopefully they will arrive early next week. We will also be doing a lot of testing and calculations throughout the design process.

To: Dave Michelson

From: EECE380 Team L2D8

Date: Feb 9th, 2014

Subject: Project 1 Weekly Memo 3

INTRODUCTION

This memo summarizes the status of the work that has been down this week, and also introduces the plan for the coming week.

ACHIEVEMENT FROM LAST WEEK

Our group has managed to send current voltage readings associated with exact time at the moment in proper format through emails. For the safety of messages, by using FFS commands, messages are saved to flash file memory while messages being sent to the satellite. Moreover, through ECE department, we placed our order of temperature sensors and DC motors which are necessary to the function of our project.

GOALS FOR NEXT WEEK

Firstly, we will try to finish what has not been done since previous weeks. Also, hopefully the parts we ordered will arrive next week, and we will start building up hardware part of the project.

To: Dave Michelson

From: EECE380 Team L2D8

Date: 2 February 2014

Subject: Project 1 Weekly Memo 2

INTRODUCTION

This memo summarizes the completion status of last week’s goal and this week’s task. It also includes the plan for the next week.

LAST WEEK’S GOALS

We successfully sent the email using satellite, and modified ADC code last week. It was planned that we should be able to send voltage readings in the emails this week. The other minor remainder of last week was to change subject line of the email. The subject line was manually changed using PuTTY command window, but the ability to change it in C code remains to be explored. On January 29th, we used CFG_Write to change the configuration parameter which is related to the subject line of the message. After debugging several errors, we managed to change the subject line to what we need. On January 31st, we combined ADC code and ORBCOMM code to send voltage readings in the emails. A floating-point number was received by the email.

THIS WEEK’S TASKS

Due to the security reason and availability of the satellite, we need to save the messages in the flash before we send it. There are two ways to approach this, one using FFS, the other using ORBCOMM saving messages commands. The other objective of this week is to familiarize ourselves with the timer on board. Later on, we may need a timer to do timely event like saving data and sending messages.

NEXT WEEK’S GOALS

First, use timer to send emails with ADC voltage readings regularly. Second, create an OSI packet, save it on board, and send it. Third, save the packet which contains voltage readings on board, and send it.

To : Dave Michelson

From :  EECE 380 Team L2D8

Date : 24 January 2014

Subject : Project 1 Weekly Memo 1

INTRODUCTION

This memo outlines the progress made during week 3 of the project as well as the problems faced.

PROGRESS

Email Sending

On the 22nd January, the teams were introduced to the overall outline of the email sending process through the satellite. We learnt to compile the code on the IAR workbench and to use QCT to upload the code to QUAKE. The debugging process is done by observing the events that were printed via the Logger port. After adding the group email to the ORBCOMM system, we attempt to send a message to the email via satellite. When we first load the unchanged DemoAppGSM code, we received no email. Therefore we attempted to debug it by checking the logger for the occurrence of important events using the printf statement. From there we discovered that the event which sends the message via ORBCOMM was not executed due to a condition in an if else statement. We then adjust the initial conditions in order for that part of the code to be executed. As a result an email with an att file attachment was received. We then proceed to initialize a char pointer for the message body as well as changing the ORBCOMM packet parameter to ORBCOMM message to get an email message instead of the attachment.

ADC

On the 24th January, we attempt to read the ADC voltage from a voltage divider through channel 0 on the logger. We modified the DemoAppsADC to read from channel 0. Initially, the voltage printed out remained constant even though the source voltage was varied. After checking the timestamp for the file loaded, we realize the file loaded was last year’s file and that the binary file we compiled was on another directory. After that we managed to get changing voltages but it was different than the actual voltage by a large margin. Therefore, we changed the conversion factor in the code to the right conversion factor and managed to get quite accurate results.

GOALS  FOR NEXT WEEK

We have decided on our meeting time every Tuesday. On the upcoming week, we planned to find a way to combine the ADC and Email Sending code to send the voltage readings to our email.

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