u-blox SARA-R4 Series System Integration Manual

Contents

SARA-R4 series - System Integration ManualUBX-16029218 - R06 Product testingPage 89 of 1025.2 Test parameters for OEM manufacturerBecause of the testing done by u-blox (with 100% coverage), an OEM manufacturer does not need to repeatfirmware tests or measurements of the module RF performance or tests over analog and digital interfaces in theirproduction test.However, an OEM manufacturer should focus on: Module assembly on the device; it should be verified that:o Soldering and handling process did not damage the module componentso All module pins are well soldered on device boardo There are no short circuits between pins Component assembly on the device; it should be verified that:o Communication with host controller can be establishedo The interfaces between module and device are workingo Overall RF performance test of the device including antennaDedicated tests can be implemented to check the device. For example, the measurement of module currentconsumption when set in a specified status can detect a short circuit if compared with a “Golden Device” result.In addition, module AT commands can be used to perform functional tests on digital interfaces (communicationwith host controller, check SIM interface, GPIOs, etc.) or to perform RF performance tests (see the followingsection 5.2.2 for details).5.2.1 “Go/No go” tests for integrated devicesA “Go/No go” test is typically to compare the signal quality with a “Golden Device” in a location with excellentnetwork coverage and known signal quality. This test should be performed after data connection has beenestablished.These kinds of test may be useful as a “go/no go” test but not for RF performance measurements.This test is suitable to check the functionality of communication with host controller, SIM card as well as powersupply. It is also a means to verify if components at antenna interface are well soldered.5.2.2 RF functional testsThe overall RF functional test of the device including the antenna can be performed with basic instruments suchas a spectrum analyzer (or an RF power meter) and a signal generator with the assistance of AT+UTESTcommand over AT command user interface.The AT+UTEST command provides a simple interface to set the module to Rx or Tx test modes ignoring the LTEsignaling protocol. The command can set the module into: transmitting mode in a specified channel and power level in all supported modulation schemes and bands receiving mode in a specified channel to returns the measured power level in all supported bandsSee the SARA-R4 series AT Commands Manual [2] and the End user test Application Note [14], for theAT+UTEST command syntax description and detail guide of usage.