VE7UWU/sdrangel
1
0
Fork 0
mirror of https://github.com/f4exb/sdrangel.git synced 2024-12-23 01:55:48 -05:00
Code Issues Projects Releases Wiki Activity

LimeSDR input: updated documentation

Browse Source
This commit is contained in:
f4exb 2017-11-05 12:48:19 +01:00
parent 83fe00d578
commit bdf5a4ef08
4 changed files with 64 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

BIN
doc/img/LimeSDRInput_plugin.png
View File

Binary file not shown.
Side by Side Swipe Overlay

Before

Width:  |  Height:  |  Size: 36 KiB

After

Width:  |  Height:  |  Size: 34 KiB

BIN
doc/img/LimeSDRInput_plugin_2.png Normal file
View File

Binary file not shown.
Side by Side

After

Width:  |  Height:  |  Size: 7.9 KiB

BIN
doc/img/LimeSDR_plugin_extclock.png Normal file
View File

Binary file not shown.
Side by Side

After

Width:  |  Height:  |  Size: 9.8 KiB

101
plugins/samplesource/limesdrinput/readme.md
View File

@ -55,52 +55,79 @@ Record baseband I/Q stream toggle button
<h4>1.4: ADC sample rate</h4>
This is the sample rate at which the ADC runs in kS/s (k) or MS/s (M) before hardware decimation (8). Thus this is the device to host sample rate (10) multiplied by the hardware decimation factor (8).
This is the sample rate at which the ADC runs in kS/s (k) or MS/s (M) before hardware decimation (8). Thus this is the device to host sample rate (5) multiplied by the hardware decimation factor (3).
&#9758; Note that changing the hardware decimation factor (8) or the device to host sample rate (10) may change the DAC clock sample rate and therefore the Tx side hardware interpolation factor and/or host to device sample rate. In fact ADC and DAC sample rates can be equal or related by a factor of 2.
&#9758; Note that changing the hardware decimation factor (3) or the device to host sample rate (5) may change the DAC clock sample rate and therefore the Tx side hardware interpolation factor and/or host to device sample rate.
<h4>1.5: Stream sample rate</h4>
Baseband I/Q sample rate in kS/s. This is the device to host sample rate (10) divided by the software decimation factor (9).
Baseband I/Q sample rate in kS/s. This is the device to host sample rate (5) divided by the software decimation factor (4).
<h4>1.6: Channel number</h4>
LimeSDR is a 2x2 MIMO device so it has two receiving channels. This shows the corresponding Rx channel index (0 or 1).
<h3>3: NCO toggle</h3>
<h3>2: NCO, DC/IQ correction and external clock controls</h3>
<h4>2.1: NCO toggle</h4>
The button is lit when NCO is active and dark when inactive.
Use this button to activate/deactivate the TSP NCO. The LMS7002M chip has an independent NCO in each Rx channel that can span the bandwidth received by the ADC. This effectively allows non zero digital IF.
<h3>4: Zero (reset) NCO frequency</h3>
<h4>2.2: Zero (reset) NCO frequency</h4>
USe this push button to reset the NCO frequency to 0 and thus center on the main passband of the ADC.
<h3>5: Center frequency with NCO engaged</h3>
<h4>2.3: Center frequency with NCO engaged</h4>
This is the center frequency of the mix of LO and NCO combined and is the source passband center frequency when the NCO is engaged. Use the thumbwheels to adjust frequency as done with the LO (1.1). Pressing shift simultanoeusly moves digit by 5 and pressing control moves it by 2. The boundaries are dynamically calculated from the LO center frequency, sample rate and hardware decimation factor.
&#9758; In the LMS7002M TSP block the NCO sits before the decimator (see Fig.14 of the [datasheet](http://www.limemicro.com/wp-content/uploads/2015/09/LMS7002M-Data-Sheet-v2.8.0.pdf) p.7) so it runs at the actual ADC rate. Hence the NCO limits are calculated as +/- half the device to host sample rate multiplied by the hardware decimation factor. For example with a 4 MS/s device to host sample rate (10) and a hadrware decimation of 16 (8) you have +/- 32 MHz span around the LO for the NCO. In this example you can tune all HF frequencies with the center frequency set at its lowest (30 MHz).
&#9758; In the LMS7002M TSP block the NCO sits before the decimator (see Fig.14 of the [datasheet](http://www.limemicro.com/wp-content/uploads/2015/09/LMS7002M-Data-Sheet-v2.8.0.pdf) p.7) so it runs at the actual ADC rate. Hence the NCO limits are calculated as +/- half the device to host sample rate multiplied by the hardware decimation factor. For example with a 4 MS/s device to host sample rate (5) and a hadrware decimation of 16 (3) you have +/- 32 MHz span around the LO for the NCO. In this example you can tune all HF frequencies with the center frequency set at its lowest (30 MHz).
<h3>6-7: Auto correction options</h3>
<h4>2.4: DC component auto correction</h4>
These buttons control the local DSP auto correction options:
Enables or disables the auto remove DC component
- **DC**: (6) auto remove DC component
- **IQ**: (7) auto make I/Q balance
<h4>2.5: I/Q balance auto correction</h4>
Enables or disables the auto I/Q balance correction
<h4>2.6: External clock control</h4>
Use this button to open a dialog that lets you choose the external clock frequency and enable or disable it. When disabled the internal 30.72 MHz VCTCXO is used.
![LimeSDR input plugin gain GUI](../../../doc/img/LimeSDR_plugin_extclock.png)
<h5>2.6.1: Exrernal clock frequency</h5>
Can be varied from 5 to 300 MHz
Use the thumbwheels to adjust frequency as done with the LO (1.1). Pressing shift simultanoeusly moves digit by 5 and pressing control moves it by 2. The boundaries are dynamically calculated from the LO center frequency, sample rate and hardware decimation factor.
<h5>2.6.2: Enable/disable external clock input</h5>
Use this checkbox to enable or disable the external clock input
<h5>2.6.3: Confirm changes</h5>
Use the "OK" button to confirm your changes
<h3>8: LMS7002M hardware decimation factor</h3>
<h5>2.6.4: Dismiss changes</h5>
Use the "Cancel" button to dismiss your changes
<h3>3: LMS7002M hardware decimation factor</h3>
The TSP block in the LMS7002M hardware has a decimation chain that acts on both Rx channels. It is composed of 5 halfband decimation stages and therefore can achieve decimation between 1 (no decimation) and 32 in increasing powers of 2: 1, 2, 4, 8, 16, 32.
Thus the actual sample rate of the ADC is the stream sample rate (10) multiplied by this factor.
Thus the actual sample rate of the ADC is the stream sample rate (5) multiplied by this factor.
<h3>9: Software decimation factor</h3>
<h3>4: Software decimation factor</h3>
The I/Q stream from the LimeSDR is doensampled by a power of two by software inside the plugin before being sent to the passband. Possible values are increasing powers of two: 1 (no decimation), 2, 4, 8, 16, 32.
<h3>10: Device to host stream sample rate</h3>
<h3>5: Device to host stream sample rate</h3>
This is the LMS7002M device to/from host stream sample rate in S/s. It is the same for the Rx and Tx systems.
@ -108,45 +135,45 @@ Use the wheels to adjust the sample rate. Pressing shift simultanoeusly moves di
The LMS7002M uses the same clock for both the ADCs and DACs therefore this sample rate affects all of the 2x2 MIMO channels.
<h3>11: Rx hardware filter bandwidth</h3>
<h3>6: Rx hardware filter bandwidth</h3>
This is the Rx hardware filter bandwidth in kHz in the LMS7002M device for the given channel. Boundaries are updated automatically but generally are from 1.4 to 130 MHz in 1 kHz steps. Use the wheels to adjust the value. Pressing shift simultanoeusly moves digit by 5 and pressing control moves it by 2.
<h3>12: TSP FIR filter toggle</h3>
<h3>7: TSP FIR filter toggle</h3>
The TSP in the LMS7002M chip has a FIR filter chain per channel. Use this button to activate or deactivate the TSP FIR filter.
<h3>13: TSP FIR filter bandwidth</h3>
<h3>8: TSP FIR filter bandwidth</h3>
USe the wheels to adjust the bandwidth of the hardware TSP FIR filter. Pressing shift simultanoeusly moves digit by 5 and pressing control moves it by 2.
<h3>14: Gain settings</h2>
<h3>9: Gain settings</h2>
![LimeSDR input plugin gain GUI](../../../doc/img/LimeSDRInput_plugin_14.png)
![LimeSDR input plugin gain GUI](../../../doc/img/LimeSDRInput_plugin_9.png)
<h4>14.1: Gain mode</h2>
<h4>9.1: Gain mode</h2>
Use this combo to select either the automatic gain (Aut) or the manual (Man) gain setting. Autonatic gain sets the global gain using a predefined table for LNA, TIA and PGA gain blocks. This global gain is set with button 14.2. When manual gain is engaged the LNA, TIA and PGA gains can be set independently with the 14.3, 14.4 and 14.5 buttons respectively.
Use this combo to select either the automatic gain (Aut) or the manual (Man) gain setting. Autonatic gain sets the global gain using a predefined table for LNA, TIA and PGA gain blocks. This global gain is set with button 9.2. When manual gain is engaged the LNA, TIA and PGA gains can be set independently with the 9.3, 9.4 and 9.5 buttons respectively.
Please refer to [LMS7002M documentation](http://www.limemicro.com/wp-content/uploads/2015/09/LMS7002M-Data-Sheet-v2.8.0.pdf) for a precise description of LNA, TIA and PGA and their location in the Rx chain. To summarize these blocks are placed in this order from antenna to ADC.
<h4>14.2: Global automatic gain</h4>
<h4>9.2: Global automatic gain</h4>
Use this button to adjust the global gain of the LNA, TIA and PGA. LimeSuite software automatically set optimal values of the amplifiers to achive this global gain. This gain can be set between 0 and 70 dB in 1 dB steps. The value in dB appears at the right of the button.
<h4>14.3: LNA manual gain</h4>
<h4>9.3: LNA manual gain</h4>
Use this button to adjust the gain of tha LNA when manual gain mode is set (14.1). Gain can be set between 1 and 30 dB in 1 dB steps. However the hardware has 3 dB steps for the lower gain values so increasing or decerasing by one step does not always produce a change. The value in dB appears at the right of the button.
Use this button to adjust the gain of tha LNA when manual gain mode is set (9.1). Gain can be set between 1 and 30 dB in 1 dB steps. However the hardware has 3 dB steps for the lower gain values so increasing or decerasing by one step does not always produce a change. The value in dB appears at the right of the button.
<h4>14.4: TIA manual gain</h4>
<h4>9.4: TIA manual gain</h4>
Use this combo to select the TIA gain in dB when manual gain mode is set (14.1). Possible values are 1,2 and 3 dB.
Use this combo to select the TIA gain in dB when manual gain mode is set (9.1). Possible values are 1,2 and 3 dB.
<h4>14.5: PGA manual gain</h4>
<h4>9.5: PGA manual gain</h4>
Use this button to adjust the gain of tha PGA when manual gain mode is set (14.1). Gain can be set between 0 and 32 dB in 1 dB steps. The value in dB appears at the right of the button.
Use this button to adjust the gain of tha PGA when manual gain mode is set (9.1). Gain can be set between 0 and 32 dB in 1 dB steps. The value in dB appears at the right of the button.
<h3>15: Antenna select</h3>
<h3>10: Antenna select</h3>
Use this combo box to select the antenna input:
@ -157,24 +184,24 @@ Use this combo box to select the antenna input:
- **T1**: Selects loopback from TX #1 (experimental)
- **T1**: Selects loopback from TX #2 (experimental)
<h3>16: Stream status indicator</h3>
<h3>11: Stream status indicator</h3>
This label turns green when status can be obtained from the current stream. Usually this means that the stream is up and running but not necessarily streaming data. The various status elements appear next on the same line (17, 18, 19)
This label turns green when status can be obtained from the current stream. Usually this means that the stream is up and running but not necessarily streaming data. The various status elements appear next on the same line (12)
<h3>17: Stream warning indicators</h3>
<h3>12: Stream warning indicators</h3>
- **U**: turns red if stream experiences underruns
- **O**: turns red if stream experiences overruns
- **P**: turns red if stream experiences packet drop outs
<h3>18: Stream global (all Rx) throughput in MB/s</h3>
<h3>13: Stream global (all Rx) throughput in MB/s</h3>
This is the stream throughput in MB/s and is usually about 3 times the sample rate for a single stream and 6 times for a dual Rx stream. This is due to the fact that 12 bits samples are used and although they are represented as 16 bit values only 12 bita travel on the USB link.
This is the stream throughput in MB/s and is usually about 3 times the sample rate for a single stream and 6 times for a dual Rx stream. This is due to the fact that 12 bits samples are used and although they are represented as 16 bit values only 12 bits travel on the USB link.
<h3>19: FIFO status</h3>
<h3>15: FIFO status</h3>
This is the fill percentage of the Rx FIFO in the LimeSuite interface. It should be zero most of the time.
<h3>20: Board temperature</h3>
<h3>16: Board temperature</h3>
This is the board temperature in degrees Celsius updated every ~5s. Before the first probe the display marks "00C" this is normal.