Siglent Integrates New Arbitrary Waveform Generator With IQ Modulation

Siglent recently introduced the new SDG8000A series arbitrary waveform generator platform.

New SDG8000A series arbitrary waveform generator. 

The two models in the series, the SDG8004A and SDG8002A, both operate with a maximum output frequency of 4 GHz at 10 Giga samples per second (GSa/s) or 5 GHz at 12GSa/s. They have a maximum sampling rate of 10 GSa/s (12GSa/s optional), 16-bit vertical resolution, and a waveform length of 2 Gpts (4 Gpts optional). The SDG8004A has four channels while the SDG8002A has two.

RF Signal Generation With IQ Modulation

One significant aspect of the new product (datasheet linked) is the inclusion of built-in, in-phase quadrature, or “IQ” modulation hardware.

Amplitude modulation was the king of RF in the early days of radio. IQ modulation has taken over that leading role in modern RF systems. IQ splits a carrier wave into sine and cosine components (90° apart), enabling modulation by both phase and amplitude. Both components are amplitude-modulated and then recombined.

The result is a significantly higher data capacity signal than traditional analog modulation techniques allow. Quadrature phase-shift keying (QPSK), for example, encodes two bits per signal (00, 01, 10, 11) instead of one bit per signal (0, 1) as is possible with digital AM or FM. Quadrature amplitude modulation (QAM) can encode up to 12 bits per signal (4,096 states).

Generating high-density IQ modulated signals is a complex operation and generally requires external equipment. The SDG8000A's inclusion of IQ modulation reduces the number of potential points of noise or signal degradation (no connectors or cables needed) and enables software-defined flexibility. The optional SigIQPro software package enables the generation of multiple protocol signals, including Wi-Fi, 5G, LTE, NR, and Bluetooth. The internal system supports up to 5 GHz RF output using the built-in hardware. This allows the new generators to create highly realistic RF and high-speed digital signals for use in development and test scenarios.

TrueArb Technology

Siglent’s proprietary TrueArb technology allows waveforms to be reproduced point by point without compromising waveform detail or low-jitter performance. The generator supports pulse generation as narrow as 250 picoseconds (PS). It is capable of multi-pulse functionality. It delivers a maximum sampling rate playback time of 800 milliseconds (ms).

Siglent waveform creation/edit dashboard. 

It integrates multi-level waveform sequence functions, including segment, sequence, and scenario. The software allows users to utilize preset waveforms or customize the presets.

Generation, Synthesis, and Advanced Sequencing Together

The SDG8000A series combines arbitrary waveform generation, direct RF signal synthesis, and IQ vector signal generation with advanced sequencing capabilities. The sequencing yields more realistic testing under changing conditions by allowing users to link, loop, and branch multiple waveforms of the same or different types. Doing so can more closely simulate real-world conditions without stopping the generator to adjust parameters.

Modulation and vector signal generation dashboard. 

In addition to standard signals, the SDC8000A line can generate a variety of special signals, including multi-pulse, multi-tone, frequency-hopping, and linear frequency-modulated (LFM) signals for use in real-world test environments. Inter-channel skew is kept below 15 ps even with differential output modes, marker outputs, external clock synchronization, and advanced triggering capabilities. That level is a must for MIMO and many synchronized RF test environments.

The generators include support for a wide variety of protocol modulation types, including the following:

• 2ASK, 4ASK, and 8ASK
• BPSK, QPSK, 8PSK, DBPSK, DQPSK, and D8PSK
• 8QAM, 16QAM, 32QAM, 64QAM, 128QAM, and 256QAM
• 2FSK, 4FSK, 8FSK, 16FSK
• MSK
• MultiTone

Software and Hardware Details

Customizability includes a robust programming interface. Siglent documentation includes instructions and examples for Visual Studio and C++, Visual Basic, MATLAB, LabVIEW, and Python.

The units include 196 built-in arbitrary waveforms. They are suitable for use in automated test suites, with USB and optional GPIB interfaces, LAN connectivity, and an internal 250-GB SSD. It includes a 1280 x 800 pixel 7-inch touchscreen display with 24-bit color. Remote control comes through an internal web server. The unit weighs in at 12.2 kg (26 lbs. 14 oz) and plots out at 426 mm × 132.5 mm × 468 mm (16.8” x 5.2” x 18.4”).

All images used courtesy of Siglent.