A typical test process on the manufacturing floor consists of various stages. At the board/panel level, system level and final testing, devices are calibrated and RF parameters are tested in non-signaling mode. Other test stages include quality assurance (QA) testing where the performance of the devices is tested in signaling mode. Rohde & Schwarz provides a one-stop solution for all production test stages.
Cellular device manufacturing


Non-signaling testing: multi-device test trends
Non-signaling tests on a production line typically include calibration followed by verification tests. Devices supporting a huge diversity of wireless communications standards ranging from 2G, 3G, 4G, WLAN, Bluetooth® and GPS to FM need to be calibrated and verified to ensure that their transmitter and receiver characteristics are in line with the tolerances specified in the relevant standard.
Since test time is a significant factor, manufacturers are constantly looking for ways to minimize both the test time and the associated costs. Parallel testing of multiple devices enables efficient use of a test instrument and increases throughput on the production line.


Multi-device testing on up to eight devices in parallel
Rohde & Schwarz offers a compact test solution for fast and efficient non-signaling testing. It consists of the R&S®CMW100 communications manufacturing test set, a compact RF shielding chamber, power supplies and the R&S®CMWrun sequencer software tool that enables automated testing on up to eight devices in parallel.


Comprehensive one-stop test solution for non-signaling testing of mobile devices
The R&S®CMW100, with a frequency range up to 6 GHz, is a multitechnology solution covering all cellular and non-cellular standards in one box. It can be used interchangeably between cellular and non-cellular test stations. Most devices have separate transceiver ports for cellular and non-cellular standards. These are directly connected to the multiports of the R&S®CMW100.
Thanks to its small form factor, the R&S®CMW100 can be located very close to the test fixture, effectively minimizing cable lengths and reducing path loss and interference. The test devices are placed inside the shielded box, which offers RF feedthroughs for direct RF connection to the ports on the device. R&S®CMWrun controls the test setup, performing RF calibration and verification tests at the board level to verify that the device’s TX and RX characteristics comply with the 3GPP specification.
Signaling testing: over-the-air testing as part of quality assurance
In the very last step of a production line, it is essential to test if mounting the antenna on the device adversely affects the performance of the device. Typically, a sample-based device test is carried out in signaling mode to simulate the device’s operation in the real world. To isolate it from interference, the device is placed in the R&S®DST200 diagnostic anechoic chamber which is large enough to accommodate various form factors such as a smartphone, router, tablet or laptop. The tests are automated using the R&S®CMWrun sequencer software tool.
This software controls the test setup, including the R&S®CMW500 wideband radio communication tester, and delivers a measurement report with results and pass/fail status indications.
Typical signaling measurements include a loopback/echo voice call or data call and a basic set of parametric TX and RX tests to verify the proper functioning of the device even after the antenna is mounted on the device. This makes it possible to detect and eliminate problems early on – an essential feature for production environments.


Test setup for testing a frontend module
Frontend module test in production
Today’s wireless communications standards are becoming more and more complex, covering an increasingly growing range of functions. This is reflected in the frontend modules (FEM) used in smartphones, where the number of integrated components, such as low-noise amplifiers and filters, is on the rise. FEMs with 16, 20, 23 or more ports are now typical.
Vector network analyzers such as the R&S®ZNBT multiport vector network analyzer from Rohde & Schwarz that offers up to 24 integrated test ports are ideal for complex RF measurements. In combination with the R&S®ZNrun automated test software, the R&S®ZNBT lets you easily keep track of the large number of measurements to be made and optimize measurement speed in an automated way.


Multi-device testing with true multiport network analyzer
Simply enter the number and types of ports of the DUT, select the measurements you want to perform and R&S®ZNrun will generate a connection plan. Now connect the DUT to the R&S®ZNBT according to the connection plan. The software takes over, performs all the tests and provides the measurement results.