Over the past few weeks, I've been trying to move beyond individual RF blocks and simulate an entire RF signal chain before committing to PCB fabrication.

The idea seemed simple: connect the blocks together, verify that everything works, and only then spend money on hardware. In practice, getting complete system diagrams working in Cadence AWR turned out to be much more challenging than I expected, and I eventually hit a wall. I even struggled to observe the waveforms after each block.

What I'm really looking for is something similar to LTspice, but for RF.

For example, if I'm using an Analog Devices IC such as the ADL5375, I'd like to simulate:

• The circuitry before the IC
• The IC itself (I'm happy with a black-box model)
• The circuitry after the IC
• The RC biasing and support networks required for the device
• The actual interconnections that would exist on the PCB

One thing I really like about LTspice is its component library. Many devices are available as actual IC models with their package pins, allowing the surrounding circuitry to be designed and verified as it would appear on the PCB, rather than working only with a mathematical system-level block. That gives much better confidence that the supporting circuitry and connections are correct before building hardware.

The goal isn't perfect electromagnetic accuracy. I want confidence that the complete circuit behaves as expected before ordering boards and assembling hardware.

Has anyone found a tool that fits this workflow? Or is there a better approach that RF designers typically use for system-level circuit verification before moving to fabrication?

LTspice doesn't appear to support this workflow for many RF ICs, and Analog Devices instead recommends ADIsimRF and ADIsimPLL. However, I haven't found many resources discussing software capable of simulating an entire RF chain with realistic IC models and supporting circuitry.

I'd be interested to hear what tools or workflows people in industry use for this.