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			57 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			57 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| <h1>File sink plugin</h1>
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| <h2>Introduction</h2>
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| 
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| This output sample sink plugin sends its samples to file in the SDRangel .sdriq format. 
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| The format is S16LE I/Q samples. Thus there are 4 bytes per sample. I and Q values are 16 bit signed integers. The file starts with a context header containing information about center frequency, sample rate and timestamp of the start of the recording. This header has a length which is a multiple of a sample size (normally 24 bytes thus 6 samples). Thus this file can be used as a raw I/Q file with S16LE samples tolerating a glitch at the start corresponding to the 6 "random" samples. For example in GNURadio you can simply specify your file source format as short complex.
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| You can also zap the 24 bytes header with this Linux command: `tail -c +25 myfile.sdriq > myfile.raw`
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| To convert in another format you may use the sox utility. For example to convert to 32 bit (float) complex samples do: `sox -r 48k −b 16 −e signed-integer -c 2 myfile.raw -e float -c 2 myfilec.raw`
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| Note that you have to specify the sampling rate and use .raw for the file extensions. 
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| <h2>Build</h2>
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| The plugin is always built.
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| <h2>Interface</h2>
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| <h3>1: Start/Stop</h3>
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| Device start / stop button. 
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|   - Blue triangle icon: device is ready and can be started
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|   - Red square icon: device is running and can be stopped
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|   - Magenta (or pink) square icon: an error occured
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|   
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| <h3>2: File stream sample rate</h3>
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| This is the file stream sample rate in kS/s after interpolation (4) from the baseband stream. Thus this is the sample rate (7) multiplied by the interpolation factor (6). 
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|   
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| <h3>3: Frequency</h3>
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| This is the center frequency in kHz that will be put in the file header.
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| <h3>4: Output file selection</h3>
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| Use this file dialog to specify the output file.
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| <h3>5: File name</h3>
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| This is the file path of the output file.
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| <h3>6: Interpolation factor</h3>
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| The baseband stream is interpolated by this value before being written to file. It can vary in powers of two from 1 (no interpolation) to 64.
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| <h3>7: Baseband sample rate</h3>
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| This is the baseband sample rate before interpolation in kS/s. Possible values are: 32, 48, 64, 72, 128, 192, 256, 288, 300, 384, 512, 1000 kS/s. 
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| <h3>8: Time counter</h3>
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| This is the recording time count in HH:MM:SS.SSS |