mirror of
https://github.com/f4exb/sdrangel.git
synced 2024-12-23 18:15:45 -05:00
131 lines
4.7 KiB
Markdown
131 lines
4.7 KiB
Markdown
<h1>Test source input plugin</h1>
|
|
|
|
<h2>Introduction</h2>
|
|
|
|
This input sample source plugin is an internal continuous wave generator that can be used to carry out test of software internals.
|
|
|
|
<h2>Build</h2>
|
|
|
|
The plugin is present in the core of the software and thus is always present in the list of sources.
|
|
|
|
<h2>Interface</h2>
|
|
|
|
|
|
|
|
<h3>1: Common stream parameters</h3>
|
|
|
|
|
|
|
|
<h4>1.1: Frequency</h4>
|
|
|
|
This is the center frequency of reception in kHz.
|
|
|
|
<h4>1.2: Start/Stop</h4>
|
|
|
|
Device start / stop button.
|
|
|
|
- Blue triangle icon: device is ready and can be started
|
|
- Green square icon: device is running and can be stopped
|
|
- Magenta (or pink) square icon: an error occurred. In the case the device was accidentally disconnected you may click on the icon, plug back in and start again.
|
|
|
|
<h4>1.4: Stream sample rate</h4>
|
|
|
|
Baseband I/Q sample rate in kS/s. This is the device to host sample rate (3) divided by the decimation factor (4).
|
|
|
|
<h3>2: Various options</h3>
|
|
|
|
|
|
|
|
<h4>2.1: Auto corrections</h4>
|
|
|
|
This combo box control the local DSP auto correction options:
|
|
|
|
- **None**: no correction
|
|
- **DC**: auto remove DC component
|
|
- **DC+IQ**: auto remove DC component and correct I/Q balance.
|
|
|
|
<h4>2.2: Decimation factor</h4>
|
|
|
|
The I/Q stream from the generator is downsampled by a power of two before being sent to the passband. Possible values are increasing powers of two: 1 (no decimation), 2, 4, 8, 16, 32. This exercises the decimation chain.
|
|
|
|
This exercises the decimation chain.
|
|
|
|
<h4>2.3: Baseband center frequency position relative to the center frequency</h4>
|
|
|
|
- **Cen**: the decimation operation takes place around the center frequency Fs
|
|
- **Inf**: the decimation operation takes place around Fs - Fc.
|
|
- **Sup**: the decimation operation takes place around Fs + Fc.
|
|
|
|
With SR as the sample rate before decimation Fc is calculated as:
|
|
|
|
- if decimation n is 4 or lower: Fc = SR/2^(log2(n)-1). The device center frequency is on the side of the baseband. You need a RF filter bandwidth at least twice the baseband.
|
|
- if decimation n is 8 or higher: Fc = SR/n. The device center frequency is half the baseband away from the side of the baseband. You need a RF filter bandwidth at least 3 times the baseband.
|
|
|
|
<h3>2.4: Sample size</h3>
|
|
|
|
This is the sample size in number of bits. It corresponds to the actual sample size used by the devices supported:
|
|
|
|
- **8**: RTL-SDR, HackRF
|
|
- **12**: Airspy, BladeRF, LimeSDR, PlutoSDR, SDRplay
|
|
- **16**: Airspy HF+, FCD Pro, FCD Pro+
|
|
|
|
<h3>3: Sample rate</h3>
|
|
|
|
This controls the generator sample rate in samples per second.
|
|
|
|
<h3>4: Modulation</h3>
|
|
|
|
- **No**: No modulation
|
|
- **AM**: Amplitude modulation (AM)
|
|
- **FM**: Frequency modulation (FM)
|
|
- **P0**: Pattern 0 is a binary pattern
|
|
- Pulse width: 150 samples
|
|
- Sync pattern: 010 at full amplitude
|
|
- Binary pattern LSB first on 3 bits from 0 to 7 at 0.3 amplitude
|
|
- **P1**: Pattern 1 is a sawtooth pattern
|
|
- Pulse width: 1000 samples
|
|
- Starts at full amplitude then amplitude decreases linearly down to zero
|
|
- **P2**: Pattern 2 is a 50% duty cycle square pattern
|
|
- Pulse width: 1000 samples
|
|
- Starts with a full amplitude pulse then down to zero for the duration of one pulse
|
|
|
|
<h3>5: Modulating tone frequency</h3>
|
|
|
|
This controls the modulating tone frequency in kHz in 10 Hz steps.
|
|
|
|
<h3>6: Carrier shift from center frequency</h3>
|
|
|
|
Use this control to set the offset of the carrier from the center frequency of reception.
|
|
|
|
<h3>7: AM modulation factor</h3>
|
|
|
|
This controls the AM modulation factor from 0 to 99%
|
|
|
|
<h3>8: FM deviation</h3>
|
|
|
|
This controls the frequency modulation deviation in kHz in 100 Hz steps. It cannot exceed the sample rate.
|
|
|
|
<h3>9: Amplitude coarse control</h3>
|
|
|
|
This slider controls the number of amplitude bits by steps of 100 bits. The total number of amplitude bits appear on the right.
|
|
|
|
<h3>10: Amplitude fine control</h3>
|
|
|
|
This slider controls the number of amplitude bits by steps of 1 bit. The signal power in dB relative to the maximum power (full bit range) appear on the right.
|
|
|
|
<h3>11: DC bias</h3>
|
|
|
|
Use this slider to give a DC component in percentage of maximum amplitude.
|
|
|
|
<h3>12: I bias</h3>
|
|
|
|
Use this slider to give an in-phase (I) bias in percentage of maximum amplitude.
|
|
|
|
<h3>13: Q bias</h3>
|
|
|
|
Use this slider to give an quadrature-phase (Q) bias in percentage of maximum amplitude.
|
|
|
|
<h3>14: Phase imbalance</h3>
|
|
|
|
Use this slider to introduce a phase imbalance in percentage of full period (continuous wave) or percentage of I signal injected in Q (AM, FM).
|