Basic Ultrasound Testing App Job Spec:

This application will run on a mobile phone and allow the detection of ultrasound signals emitted by an existing machine in an area and assist in testing it’s effectiveness. Additionally it will also enable one to test the capability of a certain mobile handset’s hardware to detect/”hear”/record certain frequencies. Functions/Features of the Application: - show amplitude of a specific frequency selected by an input text field or drop-down selector from 16kHz - 24kHz with a resolution (steps) of 500Hz (16000Hz; 16500Hz; 17000Hz; 17500Hz; [......]; 26500Hz; 27000Hz; 27500Hz; 28000Hz.) Refresh rate should be 10Hz or better without crashing the phone's processor. Amplitude measured in dB but calibration is not too important, but might be a good idea. Resolution should be in 10dB steps or better. Output can be numerical or a bar-graph. - decodes a specific basic coded signal used by an existing machine, on same frequency selected by above selector/drop-down selector. See decoding key below. To decode a string, the app should do the following: - filter all other frequencies out. - wait for a 2ms silence, then decode the string which ends with the next 2ms silence. - display decoded output for 20ms - then clear display and repeat. - optionally (this can be a separate part of the app accessible via a button or tab or menu) shows graph of all sounds picked up in the full frequency range of 16-28kHz by mobile device. This is known as a spectrum analyzer. Here is an example of what the ooutput could look like on the screen: SEE ATTACHMENT. Frequency (x-axis is 16 – 28 kHz) over Amplitude (vertically). Image is for rough conceptualization only. - App to be designed for Blackberry OS6/7, Android and iPhones. Code/decode Key The entire ultrasound code string will consist of a specific, known, fixed frequency. All other frequencies at +/- 100Hz must be ignored. 2ms silence = end/beginning of code sequence. Each sound that follows represents a digit of a string of numbers: 1ms silence = next digit follows 1ms sound = value of 1 2ms sound = value of 2 3ms sound = value of 3 [....] 9ms sound = value of 9 Code Example: 2ms silence 2ms sound 1ms silence 8ms sound 1ms silence 3ms sound 1ms silence 5ms sound 2ms silence (sequence sent by machine repeats forever) Decoded by app and displayed on screen: 2835 There will be further phases to this project as this is purely a test tool for a prototype development and testing purpose. Timeline: 1-2 weeks – Completion date: latest end March