Making real-time hardware-in-the-loop testing of automotive electronic control units wireless

Hardware-in-the-loop (HIL) simulation is an industry standard for testing automotive electronic control units (ECUs). In this paper, we present a concept that replaces the common wired cabling between a HIL test system and an automotive ECU and thus makes the real-time transmission of time-critical control, diagnostics, and calibration (CoDiCa) data wireless. This increases the flexibility of the HIL test setup and opens up new possibilities for testing automotive ECUs or autonomous driving systems. The proposed wireless communication gateway system adopts the robust physical layer IEEE 802.11p and is designed for operation in the 2.4 GHz industrial, scientific, and medical frequency (ISM) frequency band. To achieve compliance with the European regulations on spectrum access in this unlicensed band and to enable the bidirectional deterministic transfer of CoDiCa data, a new adaptive spectrum access procedure and time-slotted communication scheme is introduced. Based on extensive link-level simulations it is demonstrated that the introduced approach is able to meet the required real-time performance and hence is suitable to be applied for novel HIL test applications.