Open topic with navigation

Custom IQ - FSK

Quick Setups

Use this drop-down menu to select a modulation type from several supported formats. A single data segment using that modulation type appears in the segment list below. Click the cell in the Constellation column to open the Constellation Setting window, providing a graphical display and editing features (video). Quick setups enable you to configure complex signals for signal generation, equivalent to 89600B VSA setups in signal analysis.

Quick Setups IQ Settings

* For APCO25 CQPSK and ARIB T98/T61, the ALC is set to off to achieve better EVM. For all other cases, the ALC is on.

Save to 89600 VSA Setup

This feature saves the Custom IQ configuration as an 89600B VSA setup file, making it easier to configure complex constellations, such as 256APSK.

For added convenience, you can save the VSA setup as a quick setup in the VSA's Custom IQ Demod Property window. To do this, recall the Signal Studio VSA setup file, perform the measurement, and then click Save As Quick Setup. Now, whenever you click Quick Setups, you will find your previously saved setup listed among the other setups provided with the VSA software. Using this method, you no longer need to recall the Signal Studio VSA setup file each time you want to perform a measurement.

1. Custom IQ Selection

Custom IQ Type

Choices: ASK & PSK & QAM | FSK | SOQPSK | ARTM Multi-h CPM | Analog Modulation | Radar | Channel Sounding

Default: ASK & PSK & QAM

Select the type of Custom IQ.

FSK Settings

FSK Type

Choices: 2-FSK | 4-FSK | 8-FSK | 16-FSK | 32-FSK | 64-FSK | MSK

Default: 2-FSK

Selects the FSK type.

FSK Deviation Reference

Range: 0 - SymbolRate * 10 (Max 4GHz)

Default: 1 MHz

Sets the FSK deviation reference.

Symbol Rate

Range: 1 ksps - 4 Gsps

Default: 1 Msps

Sets the symbol rate of the FSK signal.

Filter

Choices: Gaussian | Root Nyquist | Nyquist | Rectangle | APCO25 C4FM | APCO25 HCPM | ARIB T 102 | NXDN | User Defined

Default: Rectangle

Selects the FSK filter type.

Length(symbol)

Range: 1 - 2048

Default: 32

Sets the length of the filter in symbols.

Alpha

Range: 0.01 to 1.0

Default: 0.5

Sets the alpha factor of the Root Nyquist or Nyquist filter.

BT

Range: 0.1 to 1.0

Default: 0.5

Sets the BT product of the Gaussian filter.

Filter Coefficient

Opens a Filter Editor window where you can import, export, and edit filter coefficients. A convenient plot of the filter's impulse response is displayed and updates as coefficients are changed. Imported and exported coefficient files are in text (*.txt) or comma-separated values (*.csv) format.

Payload Data

Choices: PN9 | PN15 | PN23 | Custom Bit Pattern | User File

Default: PN9

Opens the Data Setup editor to configure payload bits.You can also load, save, and create custom bit patterns.

PN Seed is in hexadecimal format and is applicable only to PN types (PN9, PN15, and PN23).

Offset is in decimal format and is applicable to all data types (including PN9, PN15, PN23, custom pattern, and user file).

Number of Symbols

Range: 100 to 8388608

Default: 1000

Sets the length of the FSK symbols.

Idle Interval

Range: 0 - 200 ms

Default: 0 us

Sets the idle interval in-between FSK frames in seconds. When the idle interval is set to zero, a continuous waveform will be generated.

Ramp Symbols

Range: 0 - 20

Default: 0

Sets the number of ramp symbols for burst signal (Idle Interval is not zero).

Reset to Default

Resets Frequency Deviation Value to default value in the table below.

Symbol

Displays the FSK symbol.

Frequency Deviation Value

Range: -FSK Deviation Reference - FSK Deviation Reference

Set the FSK deviation value for each FSK symbol.

Frequency Deviation (%)

Range: -100 - 100

Set the FSK deviation by percentage for each FSK symbol.