Electronic systems have been an important part of many cars since the 1970s, but today’s connected cars are reaching new levels of capability and complexity. Cars now resemble sophisticated, highly networked computers. An essential part of their operation entails reliable, efficient wireless communications using a variety of technologies including Wi-Fi, Bluetooth, ultra-wideband (UWB), near field communications (NFC) and 5G.

Every wireless feature, from digital keys to infotainment, must work perfectly to ensure user safety and security, and to deliver a positive experience for drivers and passengers. To achieve this level of reliability, testing of automotive wireless systems must be comprehensive and well-planned. In this blog, we’ll look at the importance of parametric testing and how automotive OEMs and Tier 1 suppliers can strengthen their wireless testing strategies.

What is Wireless Parametric Testing?

RF testing can be classified into two types. The first, protocol testing, ensures that a device is compliant with relevant standards, such as Wi-Fi or 5G, and that the device can correctly interoperate with other products.

In contrast, parametric testing is the process of measuring and verifying critical RF parameters to ensure wireless modules meet performance, safety and compliance requirements. These parameters can include transmit (Tx) power, receive (Rx) strength, frequency accuracy, packet error rate (PER), and error vector magnitude (EVM), which is the deviation of an ideal signal from the actual transmitted or received signal.

We can group automotive wireless applications into three main areas: access/digital keys, infotainment, and vehicle-to-everything (V2X) communications. For each of these application areas, parametric testing can ensure that the wireless system is performing at the required level.

The most popular wireless technologies each have their own benefits and test challenges, and are best suited to particular applications:

• Wi-Fi and Bluetooth: Widely used in vehicles for infotainment, hands-free calling, and data transfer. In-vehicle testing can be difficult due to dense RF environments with many interfering signals.
• UWB and NFC: Primarily used for digital keys and secure access to precisely establish distances. Testing challenges include the level of accuracy required and issues associated with NFC’s short range.
• 5G and 4G LTE: Increasingly used for autonomous navigation and cloud-based services. Testing can be complex and expensive, although pre-certified modules are available that help save time and money.

Why Wireless Testing Is Critical in Automotive Design 

Parametric test is essential in automotive wireless communications. For a start, it ensures high levels of quality assurance and can detect hardware defects early to prevent costly recalls of vehicles in the field.

Parametric tests also ensure drivers are safe and vehicles are secure, with reliable operation of UWB-based digital keys. Effective testing additionally guarantees seamless functioning of infotainment systems and a good user experience. Finally, parametric test ensures regulatory compliance to meet RF standards and avoid performance penalties.

As mentioned earlier, parametric test is often used for the standard, and most common, elements in an RF system: Tx power, Rx strength, frequency error, EVM for Wi-Fi, PER for Bluetooth and sensitivity checks. Technology-specific tests include UWB ranging and antenna delay calibration, as well as NFC communication integrity tests based on NFC Forum standards, and cellular module tests for 4G/5G and C-V2X performance.

Test strategies must also have the flexibility to support validation at different stages – from R&D and bench testing to end of line (EoL) production tests performed at the end of the manufacturing process.

Risks of Sub-standard Testing

While the benefits of parametric wireless test are clear, what are some of the problems if tests are skipped or conducted poorly? These can include:

• System failures: Unreliable pairing, connection drops, and miscommunication between devices
• Security: Malfunctioning digital key systems may compromise vehicle access
• Costly recalls: Fixing wireless failures post-production is far more expensive than addressing them during design
• Brand damage: Negative user experiences lead to bad reviews and loss of trust
• Safety: In autonomous vehicles, poor 5G/LTE connectivity can cause navigation errors and failures

Making Wireless Test Work for You

Taking all these factors into account, how can automotive companies strengthen wireless testing? First, they should adopt a design-to-production mindset, starting test activities early in the design phase rather than waiting until later development. 

Using standardized test checklists ensures that all core RF parameters are consistently validated, reducing the risk of missed issues. Test data can then be leveraged with analysis tools to fine-tune device performance, helping engineers detect and resolve problems more efficiently.

To further reduce costs and shorten development timelines, parallel or batch testing can be adopted to increase throughput. Advanced parallel/batch testing reduces test time and cost without compromising quality, thus improving production efficiency.

Finally, strategic collaboration with experienced partners such as LitePoint provides access to turnkey solutions that simplify complex wireless testing challenges. For example, LitePoint’s IQfact+ Test Automation solutions support parametric measurements for automotive Wi-Fi, Bluetooth and UWB, ensuring phase accuracy, power control and throughput validation in production environments. 

LitePoint works directly with chipset vendors to pre-validate test software and methods, providing silicon-to-production continuity. It provides global expertise and proven automotive experience with on-site support across key manufacturing locations ensuring consistent testing quality. 

In conclusion, parametric wireless testing is not optional – it underpins safety, reliability, and customer satisfaction in connected vehicles. To meet consumer expectations across the spectrum of wireless features, automotive OEMs and Tier 1 suppliers should invest in robust parametric testing frameworks, leveraging expert partners like LitePoint to streamline processes and minimize risks.