The ARB (Arbitrary Waveform) function in the Bird GenHawk GH-60 Handheld Signal Generator allows you to generate custom RF signals at any carrier frequency between 10 MHz and 6 GHz (optionally 300 kHz to 6.5 GHz).
Arbitrary waveforms are used by engineers and technicians to produce consistent, custom test signals during testing. The GH-60's ARB capability is ideal for generating short, repeatable RF prompts for verifying signal immunity or response.
Playing Arbitrary RF Signals
- Start by Loading your ARB files onto the GH-60s internal file system. We discuss how to make these data files later.
- From the GenHawk application, set your desired carrier frequency and amplitude.
- Open the ARB module, available as an optional license, MTX-S009.
- Select the file type that matches your ARB file/s from the following option. This example will use Txt file type.
- Select the file format of your ARB files (for Txt and Binary file types). A single file of interleaved I and Q data, or two separate I and Q files. Files can also be ordered as IQ or QI.
- Select the appropriate data file(s) to import.
- Set your Clock Rate in Mega Samples per second to match the sample clock used in the file (e.g. 1 MS/s). Clock rate can be set between 1-250 MS/s.
- Adjust the Data Length setting to match the total number of complex samples in your data.
The total time of the signal cannot exceed 75 ms in length, this is defined by Clock Rate and Data Length i.e. if the Clock Rate is 1 MS/s, the maximum Data Length is 75,000 samples. - Tap the ✓ check‑mark in the upper right to load the data, this might take some time depending on Data Length.
- Press RF Out ▸ ON to begin playback.
Supported File Types
The GH-60 utilizes IQ (In-Phase / Quadrature) data to generate arbitrary RF signals. IQ data is a robust way to define RF behavior that's supported by most RF editing programs and can be generated by custom programs.
|
File Type & Format |
Data type |
|
Binary + 1 File IQ |
Format data point as int16 |
|
Binary + 2 File |
Format data points as int16 |
|
Txt + 2 File |
IQ files saved as .txt containing ASCII signed numbers centered at 0. |
|
Txt + 1 File IQ |
IQ files saved as .txt containing ASCII signed numbers centered at 0. Samples will consist of two numbers alternating between I and Q values, starting with the first I value followed by the first Q value. |
|
R&S .wv data file |
Supported, but not documented here. |
Example Files and Tools
You can create files however you like, but Bird has constructed some examples to help:
- ARB_data_gen.py generates binary I and Q files for an FM signal.
- ARBfile.py converts I and Q binary files into .txt files.
-
fm_audio_sweep_i.txt and fm_audio_sweep_q.txt create a modulated FM audio signal.
These files output a 75 ms audio chirp that sweeps from 30 Hz to 15kHz. If the signal is sent to a FM radio or FM demodulator, it will play a short chirping sounds as the frequency increases across the audio spectrum and loops every 75 ms.
Looking to simplify signal generation?
Learn how the GenHawk GH-60 Signal Generator makes generating complex RF signals easy, from generic AM/FM to cellular and IoT standards.
Download the GenHawk Modulation Options technical brief to explore all supported modulations.
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