What is in this article?:
- Testing Automotive Radar Brings mm-Wave Challenges
- A Matter Of Power
The growing number of 77-GHz automotive radar systems has put pressure on RF/microwave test-and-measurement-equipment manufacturers to develop cost-effective measurement solutions for these systems.
A Matter Of Power
Of course, testing these systems and their components at millimeter-wave frequency bands such as 76 to 77 GHz requires the generation and analysis of pulsed millimeter-wave frequencies at sufficient power levels. Signal sources for such high frequencies are usually produced with the aid of frequency doublers and triplers, while analyzers rely on frequency-downconversion techniques for such instruments as spectrum analyzers. Most major instrument makers, including Agilent Technologies, Anritsu Co., Rohde & Schwarz, and Tektronix, offer solutions for testing at automotive millimeter-wave frequencies.
Even smaller instrument suppliers, such as Roos Instruments, offer testers for 77 GHz, including the firm’s model RI8564A test set. Based on a modular approach to instrumentation, the company’s instrument solutions work with tester instrument modules (TIMs) to achieve the required functionality for a number of different automotive radar tests at 77 GHz. For example, tests with Roos’ Cassini modular automatic-test-equipment (ATE) systems include efficiency (for power amplifiers, full S-parameter measurements, output power at 1-dB compression, third-order intermodulation (IM3), and leakage current.
Some of the essential measurements required for automotive radars at 76 to 77 GHz include system-level tests such as transmit and receive frequencies and frequency bandwidths, transmit and receive power levels, modulation, radar system measurement distance and resolution, antenna beamwidth, and power supply requirements. Additional measurements tend to apply to component-level testing, such as gain and noise figure for amplifiers and phase noise, spurious levels, and harmonic levels for signal sources. Many of the leading test-and-measurement equipment suppliers offer benchtop solutions, with signal generators and analyzers (such as spectrum analyzers, scalar network analyzers, and vector network analyzers), for measurements through 79 GHz. However, the availability of portable 77-GHz measurement systems for automotive radar testing was been extremely limited to this point.
Yet such portable measurement capabilities will be invaluable to automotive manufacturers and service shops as the number of automotive radar systems worldwide increases. The challenge for test-equipment suppliers will be to supply such traditionally exotic millimeter-wave measurement capabilities to automotive customers in need of watching tight budgets.