System and method for parallel RF transceiver testing and characteristic analysis

Abstract

The invention relates to a system and method for parallel RF transceiver testing and characteristic analysis. A test system (100) includes: a test instrument (102) having a signal terminal (103); a distributor (104) having a distributor input connected to the signal terminals (103) and a plurality of distributor outputs (105, 106, 107, 108); a plurality of test channels (111, 121, 131, 141), each test channel including a receptacle (113, 123, 133, 143) having a receptacle terminal connected to a respective one of the dispenser outputs (105, 106, 107, 108) to couple a transceiver terminal (112, 122, 132, 142) of a mounted electronic device under test (DUT) to the respective dispenser output (105, 106, 107, 108); and a controller (150) configured to operate the test instrument (102) to concurrently test transceiver circuits (114, 124, 134, 144) of the installed DUT under respective unique subcarriers of an OFDM signal at the signal terminal (103).

Description

Technical Field

[0001] The present application relates to the field of circuit technology, and more particularly, to systems and methods for parallel RF transceiver testing and characterization. Background Art

[0002] Testing radio frequency (RF) transceiver circuit operation is a critical aspect of integrated circuit manufacturing, ensuring that manufactured electronic devices operate correctly. RF transceiver testing is also beneficial during product design verification and manufacturing method development. Testing multiple devices in parallel reduces costs and increases manufacturing throughput, shortening development-to-market time. However, unlike digital or analog circuit testing, manufacturing test systems typically have far fewer RF test resources than digital test resources, and RF measurement hardware is more expensive than digital test equipment. Low parallelism leads to lower throughput and, therefore, higher test costs. Adding an RF switch matrix allows serial testing of multiple devices under test (DUTs), but does not significantly reduce overall test time. Summary of the Invention

[0003] In one aspect, a test system includes a test instrument having signal terminals and a splitter having a splitter input connected to the signal terminals of the test instrument and a plurality of splitter outputs. The system has test channels, each test channel including a receptacle having a receptacle terminal connected to a respective one of the splitter outputs to couple a transceiver terminal of a mounted electronic device under test (DUT) to the respective splitter output; and a controller configured to operate the test instrument to concurrently test the transceiver circuits of the mounted DUTs under respective unique subcarriers of an orthogonal frequency division multiplexing (OFDM) signal at the signal terminals.

[0004] In another aspect, a method of manufacturing electronic devices includes: installing the manufactured electronic devices in respective sockets, wherein the transceiver circuit of each respective electronic device is connected to a respective splitter output of a splitter; and operating a single test instrument to concurrently test the transceiver circuits of the installed electronic devices under respective unique subcarriers of an OFDM signal at a signal terminal of the test instrument. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 A system diagram illustrating a parallel test system for parallel testing of RF transceivers of a DUT with an integrated device modem, the parallel test system having a single test instrument and an RF splitter.

[0006] Figure 2 A flow chart of a method for manufacturing an electronic device.

[0007] Figure 3A system diagram illustrating another parallel test system for parallel testing of RF transceiver DUTs is shown. The system has test instruments, an RF splitter, and multiple system channel OFDM modems.

[0008] Figure 4 FIG. 4 is a partial signal diagram of an example OFDM spectrum with 52 subcarriers, including 48 data subcarriers and 4 pilot subcarriers.

[0009] Figure 5 An example subcarrier assignment is shown, where each of the four DUTs under test is assigned a unique group of ten data subcarriers.

[0010] Figure 6-9 Respective transceiver transmission test waveforms generated by four DUTs under test under respective assigned unique subcarrier groups are shown.

[0011] Figure 10 The received composite OFDM signal is shown as received by the test instrument during a parallel transmission test on four DUTs. DETAILED DESCRIPTION

[0012] In the drawings, similar reference numerals refer to similar elements throughout, and the various features are not necessarily drawn to scale. In addition, the term "couple" or "couples" includes indirect or direct electrical or mechanical connections, or a combination thereof. For example, if a first device is coupled to or coupled with a second device, the connection may be a direct electrical connection, or it may be an indirect electrical connection via one or more intervening devices and connections. One or more operating characteristics of various circuits, systems, and / or components are described below in the context of functionality, which in some cases is generated by the configuration and / or interconnection of various structures when the circuit system is powered and operating. Example structures include a layer or material described as being above or on another layer or material, which may be a layer or material directly on and in contact with the other layer or material, wherein other materials (e.g., impurities or artifacts or residual materials from the manufacturing process) may be present between the layer or material and the other layer or material. Unless otherwise stated, "about," "approximately," or "substantially" preceding a value means + / - 10% of the value. For ease of description in conjunction with certain figures, one or more structures, features, aspects, components, etc. may be referred to herein as first, second, third, etc., wherein such structures, features, aspects, components, etc. should not be construed as limiting the claims. The various disclosed structures and methods of the present disclosure can be advantageously applied to electronic devices, manufacturing, testing, and / or operating electronic devices such as integrated circuits. Although such examples can be expected to provide various improvements, the present disclosure does not require a specific result unless explicitly recited in a particular claim.

[0013] Figure 1 A parallel test system 100 for parallel testing of RF DUTs is shown having a single test instrument 102 (e.g., Figure 1 ). The test instrument 102 has signal terminals 103 adapted to receive RF signals transmitted by the DUT under test on multiple subcarriers of an orthogonal frequency division multiplexing (OFDM) spectrum during parallel transceiver transmit testing, and to transmit RF signals to the DUT under test on OFDM subcarriers during RF transceiver receive testing. Any suitable test instrument 102 may be used, such as an RF signal analyzer capable of analyzing specific subcarrier signals of OFDM or other suitable modulated signals at the signal terminals 103 for testing the transmit operation of the DUT under test, and capable of providing OFDM output signals at the signal terminals 103 for testing the receive operation of the DUT. Furthermore, in certain embodiments, the test instrument 102 may include multiple devices, such as one device for receiving and analyzing OFDM signals for testing the transmit operation of the installed DUT and a second device for transmitting OFDM signals for testing the receive operation of the installed DUT.

[0014] Figure 1The test system 100 in FIG. 1 is configured for parallel testing of RF transceivers of a device under test (DUT) having an integrated device modem. System 100 includes an RF splitter 104 (e.g., labeled as an "RF combiner / splitter"), which may also be referred to as a power splitter, power divider, power combiner, or "splitter or combiner," and is hereinafter referred to as a splitter. Splitter 104 has one splitter input and N splitter outputs 105-108, where N is an integer greater than 1, and even though referred to as a "splitter," splitter 104 may be used as an RF splitter and / or as an RF combiner for respective receive and transmit testing of RF transceiver DUTs. The splitter input is connected to a signal terminal 103 of a test instrument 102. In one example, RF splitter 104 is a passive component or system having N ports connected to a transmission line at the splitter input and to the splitter outputs for coupling electromagnetic power from the splitter input to respective splitter outputs 105-108. The RF splitter 104 may include one or more directional couplers, hybrids, coupled transmission lines, waveguide designs, or other coupling structures to combine RF DUT signals from the splitter outputs 105-108 to the splitter input and the signal terminal 103 of the test instrument 102 for DUT transmission testing, and / or to couple the power of the RF signal transmitted by the test instrument 102 to the signal terminal 103 and the splitter input to the splitter outputs 105-108 for DUT reception testing. In one embodiment, the ports or splitter outputs 105-108 can be isolated from each other. The RF splitter 104 enables parallel DUTs to be tested concurrently using the RF signals at the splitter inputs for reception testing, and enables the test instrument 102 to use a combination of RF signals from the DUTs during DUT transmission testing.

[0015] The test system 100 has a reference clock 109 having a clock output 110 that provides a shared clock signal for use by the DUT and other circuitry of multiple test channels. The distributor 104 can be connected to the test channels via a wired or wireless connection. The example system has N=4 test channels, including a first test channel 111 (e.g., Figure 1105, 106, 107, and 108 for coupling the transceiver terminals 112, 122, 132, and 142 of an installed electronic DUT to the corresponding splitter outputs 105, 106, 107, and 108.

[0016] In this example, the first test channel 111 receives a first DUT in a first socket 113. In this example, the first socket 113 includes a first data terminal 117 adapted to connect a first data line to a data terminal of the first DUT. Figure 1 As schematically shown in FIG, in this example, the DUT has internal transceiver circuitry 114 (e.g., labeled "TX / RX") having transmit and receive terminals connected to transceiver terminals 112 of a first test channel 111 via transceiver terminals of a first socket 113. The DUT in the first test socket 113 includes an internal connection 115 from the first transceiver circuitry 114 to a first modem 116 of the first DUT. The modem 116 is operatively coupled to the transceiver circuitry 114 of the first test channel 111. The first modem 116 has a clock input connected to a clock output 110 of a shared reference clock 109, and a data terminal connected to a first data terminal 117 of the first socket 113. The other DUT modems have similar operative connections to the transceiver circuitry of the respective DUTs and are all connected to the shared system reference clock 109.

[0017] The second test channel 121 accommodates a second DUT in a second socket 123. In this example, the second socket 123 includes second data terminals 127 adapted to connect a second data line to a data terminal of the second DUT. Figure 1As schematically shown in FIG, a second DUT is installed having internal transceiver circuitry 124 with transmit and receive terminals connected to transceiver terminals 122 of a second test channel 121 via transceiver terminals of a second socket 123. The DUT in the second test socket 123 includes internal connections 125 from the second transceiver circuitry 124 to a second modem 126 of the second DUT. The second modem 126 has a clock input connected to a clock output 110 of the shared reference clock 109, and a data terminal connected to a second data terminal 127 of the second socket 123.

[0018] The third test channel 131 accommodates a third DUT in a third socket 133. In this example, the third socket 133 includes a third data terminal 137 adapted to connect a third data line to a data terminal of the third DUT. The third DUT has internal transceiver circuitry 134 with transmit and receive terminals connected to transceiver terminals 132 of the third test channel 131 via the transceiver terminals of the third socket 133. The DUT in the third test socket 133 includes an internal connection 135 from the third transceiver circuitry 134 to a third modem 136 of the third DUT. The third modem 136 has a clock input connected to the clock output 110 of the shared reference clock 109, and a data terminal connected to a third data terminal 137 of the third socket 133.

[0019] The last test channel 141 (e.g., the fourth or "Nth" channel, "Channel N") houses a fourth DUT in a fourth socket 143. The fourth socket 143 has fourth data terminals 147 adapted to connect a fourth data line to the data terminals of the installed fourth DUT. The fourth DUT has internal transceiver circuitry 144 having transmit and receive terminals connected to transceiver terminals 142 of the fourth test channel 141 via the transceiver terminals of the fourth socket 143. The DUT in the fourth test socket 143 includes an internal connection 145 from the fourth transceiver circuitry 144 to a fourth modem 146 of the fourth DUT. The fourth modem 146 has a clock input connected to the clock output 110 of the shared reference clock 109, and a data terminal connected to a fourth data terminal 147 of the fourth socket 143.

[0020] System 100 includes a controller 150, such as an automatic test equipment (ATE) control processor having analog and / or digital interface circuitry, a programmed processor, and associated electronic memory. In one example, the processor of controller 150 is configured, via appropriate program instructions, to operate test instrument 102 to concurrently test transceiver circuits 114, 124, 134, and 144 of installed DUTs under respective unique subcarriers of an OFDM signal at signal terminal 103. Furthermore, controller 150 can be configured to operate the DUTs and exchange data with the installed DUTs via data terminals 117, 127, 137, and 147 and associated DUT modems 116, 126, 136, and 146. Furthermore, in certain examples, controller 150 manages subcarrier assignments for the respective DUTs, such that unique subcarriers or groups thereof are individually assigned to the DUTs installed in the respective test channels 111, 121, 131, and 141.

[0021] exist Figure 1 In the example of FIG, each respective DUT has an internal modem 116, 126, 136, 146. In another example, the DUT may be a transceiver or other electronic device that does not include an internal modem. In this example, the system may have a system modem associated with the individual test channels, and the system modem may be operated by the system controller, as described below in conjunction with FIG. Figure 3 Further explanation and description. In addition, in some examples, the system may include individual test channels having both system modems and direct data terminals for connecting the controller 150 to the system modem and / or a socket configured for a first type of DUT that includes an internal modem, wherein the system modem of each test channel is operably connected to a second channel socket configured to receive and test a DUT that does not include an internal modem (e.g., an RF amplifier or other circuit with an RF transceiver to be tested in the system). In other examples, the system 100 may include multiple sockets within each test channel to accommodate concurrent high-parallel testing (HPT) of the RF performance of different types and forms of packaged electronic devices. In this or other examples, the system 100 may include associated system modems and switching circuitry or other electrical connections to enable selective use of any included (e.g., integrated) modem or system modem for a given test channel that has a data connection to the controller 150 and each DUT's transceiver is connected to a corresponding splitter output of the RF splitter 104. These configurations and other variations advantageously facilitate parallel (eg, concurrent) RF testing of multiple DUTs using a single test and measurement instrument 102 .

[0022] Also refer to Figure 2The test system 100 implements parallel testing of multiple installed DUTs in an automated or semi-automated manner by appropriately programming the controller 150 and other system devices, such as automatic device installation and removal of DUTs installed in the channel sockets 113, 123, 133, and 143. In another example, the DUTs may be manually installed in the channel sockets 113, 123, 133, and 143 before testing and removed from the channel sockets 113, 123, 133, and 143 after testing.

[0023] System 100 may be configured for single-pass or multi-pass testing of an installed DUT for either or both transmit and receive operations of transceiver circuits 114, 124, 134, and 144. Figure 1 ), parallel testing can also verify the correct operation of modems 116, 126, 136, and 146. The controller 150 is within the bandwidth of interest for a given DUT type under test, for example, as described below. Figure 4 and 5 In the example OFDM spectrum shown, selective subcarrier assignment is implemented. In one DUT transmission test example, the controller 150 is configured to control individual DUTs to concurrently transmit on corresponding unique subcarriers and to control the test instrument 102 to analyze the individual signals of the corresponding unique subcarriers received at the signal terminal 103 of the test instrument 102. In one example, the controller 150 sends data along the corresponding data terminals 117, 127, 137, and 147 to the DUT modems 116, 126, 136, and 146 for transmission on the assigned subcarriers or assigned subcarrier groups during a given pass of the transmission test.

[0024] In this or another example, the controller 150 is configured to determine whether the transmission test result for each respective DUT is a pass or fail based on the received carrier signal strength of the respective unique subcarrier received at the signal terminal 103 of the test instrument 102. In this case, the test result indicates whether the transmission portion of the respective tested transceivers 114, 124, 134, and 144 exhibits an acceptable transmission signal strength value. In one transmission test implementation, the controller 150 performs a single transmission test pass in which each individual DUT is assigned a unique subcarrier or subcarrier group of the OFDM spectrum of interest (e.g., the following Figure 5 ), and the controller determines whether the transmission result of each tested DUT is passed or failed based on the single-pass transmission test.

[0025] In another example, the controller 150 performs multiple passes, wherein for each successive test pass, a unique subcarrier reassignment is made for each DUT (e.g., using a unique single assigned subcarrier or a unique group of two or more assigned subcarriers). In some multi-pass implementations, every subcarrier is tested for each DUT, but this is not required for all possible implementations, and fewer than all possible subcarriers may be evaluated for each DUT under test for either or both transmit and receive testing.

[0026] The system 100 can also use highly parallel single-pass or multi-pass testing to test the receiver portions of the transceivers 114, 124, 134, and 144. In one example, the controller 150 is configured to control the test instrument 102 to transmit concurrently on each of the corresponding unique subcarriers at the signal terminal 103. In this example, the controller 150 controls the modems 116, 126, 136, and 146 of each corresponding test channel 111, 121, 131, and 141 to concurrently decode the received signals of the corresponding unique subcarriers using the shared signal at the output 110 of the system reference clock 109, and the modems 116, 126, 136, and 146 each send the decoded data for each corresponding unique subcarrier or subcarrier group to the controller 150. In one example, the controller 115 is configured to determine whether the received test result for each respective DUT is a pass or fail based on the decoded data for each respective unique subcarrier, e.g., based on the number of correctly received data packets based on the known transmission data provided by the controller 150 to the modems 116, 126, 136, and 146.

[0027] In one embodiment, the controller 150 is configured to operate the test instrument 102 to concurrently test the DUT transceiver circuits 114, 124, 134, and 144 with a single pass or multiple passes under corresponding unique subcarrier groups of the OFDM signal at the signal terminal 103. In one example, the system implements IEEE 802.11 OFDM testing using 48 virtual sub-data channels (subcarriers) in one physical RF channel to provide high parallel testing (HPT) with modified OFDM, where multiple (e.g., N) DUT RF paths are synthesized to share virtual sub-data channels / carriers on the same physical RF channel.

[0028] In one example, the controller is configured to operate the test instrument 102 to perform multiple test passes using different assigned unique subcarriers or assigned unique subcarrier groups for the respective DUTs in each test pass. In these or another example, the controller 150 is configured to operate the test instrument 102 to perform a single test pass using fewer than all unique subcarriers for the respective DUTs. In another example, the controller 150 is configured to operate the test instrument 102 to perform multiple test passes using fewer than all unique subcarriers for the respective DUTs. The system 100 enables highly parallel testing of subcarriers for each DUT when desired, and can implement incomplete subcarrier testing for each DUT to increase throughput and reduce test time for a batch of DUTs.

[0029] Figure 2 A method 200 of manufacturing an electronic device according to another aspect is shown. The method 200 includes Figure 2 The DUT is mounted in the corresponding sockets 113, 123, 133 and 143 at 202 in the embodiment, wherein the transceiver circuits 114, 124, 134 and 144 of each corresponding electronic device are connected to Figure 1 The method 200 includes operating a single test instrument 102 to concurrently test the transceiver circuits 114, 124, 134, and 144 of the installed electronic DUT under corresponding unique subcarriers of the OFDM signal at the signal terminal 103 of the test instrument 102.

[0030] In the illustrated example, the controller 150 determines whether a DUT transmission test is required at 204. If required (yes at 204), the controller 150 Figure 2 Automated transmission testing is performed at 206, 208, and 210 in FIG. In one example, the transmission testing includes the controller 150 operating the integrated DUT modems 116, 126, 136, and 146 while concurrently testing the transceiver circuits 114, 124, 134, and 144 of the installed electronic DUTs, the modems being integrated (e.g., included) in the respective DUTs and operably coupled to each respective transceiver circuit 114, 124, 134, and 144. In another example, the controller 150 operates as follows: Figure 3 The system modem is shown external to the DUT under test, while concurrently testing the DUT transceiver circuitry to which the system modem is connected.

[0031] in 206 and Figure 2At 208, the controller 150 controls the individual electronic DUTs to concurrently transmit on the respective assigned unique subcarriers (a single assigned subcarrier or a group of unique assigned subcarriers), for example, to transmit data provided by the controller 150 to the respective modems 116, 126, 136, and 146 via the respective data terminals 117, 127, 137, and 147. At 208, the controller 150 controls the single shared test instrument 102 to analyze the individual signals of the respective unique subcarriers received at the signal terminal 103 of the test instrument 102. At 210, in the illustrated example, the controller 150 determines whether the transmission test result for each respective electronic DUT is a pass or fail based on both the received carrier signal strength of the respective unique subcarriers received at the signal terminal 103 of the test instrument 102 and the decoded error vector magnitude (EVM) parameters (e.g., power amplitude and modulation quality) of the respective unique subcarriers received at the signal terminal 103 of the test instrument 102. In one example, the controller 150 calculates the vector magnitude error parameter based on a distance between an ideal target constellation (eg, in the IQ plane), which represents the magnitude of the modulation quality error.

[0032] In one example, the controller 150 compares the individual received carrier signal strength of each assigned subcarrier at 210 with a corresponding pass or fail threshold (e.g., a power amplitude threshold) and compares the decoded EVM parameter of the corresponding unique subcarrier received at the signal terminal 103 with a predetermined EVM threshold (e.g., a modulation quality threshold). In this example, if the received signal strength is less than the power amplitude threshold or if the decoded EVM is equal to or greater than the predetermined modulation quality threshold, the controller 150 determines that the transmission test result is a fail, otherwise the controller 150 determines that the corresponding DUT to which the subcarrier is assigned passes the transmission test. In the event that two or more subcarrier groups are currently assigned to a given DUT, in one example, if any received signal strength of the assigned subcarrier group is less than the corresponding power amplitude test threshold, or if any decoded EVM parameter is equal to or greater than the predetermined modulation quality threshold, the controller 150 determines that the transmission test result is a fail. In some embodiments, the tests at 206-210 may be repeated for further passes, e.g., reassigning subcarriers for the respective DUTs between consecutive passes, to perform multiple test passes using different assigned unique subcarriers or groups of assigned unique subcarriers for the respective electronic DUTs in each test pass.

[0033] If DUT transmission testing is not being performed (No at 204) or after all required single-pass or multi-pass transmission testing is completed, method 200 proceeds to Figure 2212, where the controller 150 determines whether the DUT reception test is required. If not required (no at 212), the DUT is uninstalled or otherwise removed from the sockets 113, 123, 133, and 143 at 220, and the method 200 may be repeated for another set of DUTs.

[0034] If a reception test is required (yes at 212), the controller 150 Figure 2 Automated receive testing of the DUT transceiver circuits 114, 124, 134, and 144 is performed at 214, 216, and 218 in FIG. In one example, the receive test comprises a single-pass test. In another embodiment, the receive test can be performed in multiple passes, for example, with subcarriers reassigned between test passes. In one example, at 214, the controller 150 controls the test instrument 102 to concurrently transmit on each of the corresponding assigned unique subcarriers at the signal terminal 103.

[0035] At 216, the controller 150 controls the integrated DUT modems 116, 126, 136, and 146 (or as described below) of each respective test channel 111, 121, 131, and 141. Figure 3 Also at 216, modems 116, 126, 136, and 146 send the decoded data for each respective unique subcarrier to controller 150 for evaluation.

[0036] At 218, the controller 150 determines whether the received test result for each respective electronic device is a pass or fail based on the decoded data for each respective unique subcarrier. In one example, the controller 150 compares the decoded data packets from the modems 116, 126, 136, and 146 for the respective subcarriers with the data packets provided to the test instrument 102 and determines the number of incorrectly decoded data packets from the modems 116, 126, 136, and 146 at 218. In this example, if the number of incorrectly decoded data packets is equal to or greater than a predetermined test threshold, the controller 150 determines the received test result for each respective DUT and the assigned subcarrier (or subcarrier group) as a fail at 218, otherwise determines the received test result as a pass.

[0037] The controller 150 may be programmed or otherwise configured to implement different test pass or fail criteria for either or both transmit and receive tests. In certain embodiments, the receive tests at 214-218 may be repeated for further passes, for example, reassigning subcarriers to the respective DUTs between successive test passes to perform multiple test passes using different assigned unique subcarriers or assigned unique subcarrier groups for the respective electronic DUTs in each test pass. Once all required receive tests have been performed, the DUTs under test are unloaded from the respective test sockets 113, 123, 133, and 143 at 220.

[0038] Figure 3 Another parallel test system 300 is shown having a single test instrument 102 and an RF splitter 104 having an example set of N=4 channels 111, 121, 131, and 141 substantially as described above, except that the DUTs under test include corresponding transceiver circuits 114, 124, 134, and 144 as described above. However, in this example, the transceivers are tested using system OFDM modems 316, 326, 336, and 346 operatively coupled to the respective channels 111, 121, 131, and 141 for highly parallel testing of RF transceiver DUTs, wherein the modem 316, 326, 336, 346 of each respective test channel 111, 121, 131, and 141 is external to the respective DUT. This system embodiment 300 can be used, for example, to test DUTs that do not include an internal modem. In another example, the test system 300 can be used to test transceiver circuits 114, 124, 134, and 144 of a DUT having an internal modem and requiring separate testing of the transceiver circuits using the external system modems 316, 326, 336, and 346 of the corresponding test channels. In the illustrated system 300, the test channels 111, 121, 131, and 141 include corresponding channel sockets 313, 323, 333, and 343 having corresponding socket terminals 115, 125, 135, and 145 to connect the corresponding transceiver circuits 114, 124, 134, and 144 to the corresponding system channel modems 316, 326, 336, and 346, as shown. Figure 3 The system includes individual channel data terminals 317 , 327 , 337 , and 347 that connect the controller 150 to the corresponding data terminals of the system modems 316 , 326 , 336 , and 346 .

[0039] Also refer to Figure 4 and 5 , Figure 4A portion of a signal diagram 400 of an example OFDM spectrum signal waveform or spectrum 401 is shown having 52 subcarriers labeled 402, correspondingly labeled +1 to +26 and -1 to -26, one null subcarrier denoted as "0," and four pilot (BPSK) subcarriers including 48 data subcarriers and 4 pilot subcarriers +7, +21, -7, and -21. The example OFDM spectrum 401 extends within a 20 MHz bandwidth 403 including a 16.6 MHz orthogonal bandwidth 404. The test systems 100 and 300 and the method 200 can operate in any bandwidth of interest using corresponding subcarriers for high parallel RF testing. Figure 4 The spectrum 400 in FIG. 4 is a non-limiting illustrative example. Figure 5 An example subcarrier assignment diagram 500 is shown in which each of the four DUTs under test in the example test systems 100 and 300 described above using N=4 is assigned a unique group of ten data subcarriers 501, 502, 503, and 504 for one example test pass for either receive or transmit testing.

[0040] Figure 5 The example channel assignments shown can be used by the controller 150 for a single-pass test of four DUTs, or for the first pass in a multi-pass implementation where the subcarrier assignments are changed within successive test passes. In this example, a first subcarrier group 501 is used to test a first DUT transceiver circuit 114 in a first channel 111 and includes subcarriers -16, -17, -18, -19, -20, -22, -23, -24, -25, and -26. The controller 150 assigns a second example subcarrier group 502 to a second channel 121 to test a second DUT transceiver circuit 124 in the second channel 121 and includes subcarriers -2, -3, -4, -5, -6, -8, -9, -10, -11, and -12. In this example, the controller 150 assigns a third subcarrier group 503 to test the third DUT transceiver circuit 134 of the third channel 131 and includes subcarriers 2, 3, 4, 5, 6, 8, 9, 10, 11, and 12. In this example, a fourth subcarrier group 504 is used to test the fourth DUT transceiver circuit 144 of the fourth channel 141 and includes subcarriers 16, 17, 18, 19, 20, 22, 23, 24, 25, and 26. This example grouping utilizes the full capability of a single shared test instrument 102, which can evaluate the received signal on each subcarrier for transceiver transmit testing, and also facilitates thorough receive testing, where the test instrument 102 can transmit on all data subcarriers simultaneously in a single pass or first pass for evaluating decoded data received by the receiver circuit of the DUT under test.

[0041] In one example, the assigned subcarrier groups are rotated among channels 111, 121, 131, and 141 for the next pass of a multi-pass implementation. For example, the controller 151 may implement the second pass by assigning subcarrier group 501 to the second channel 121, subcarrier group 502 to the third channel 131, subcarrier group 503 to the fourth channel 141, and subcarrier group 504 to the first channel 111. The rotation of the assignment of subcarrier groups 501-504 is one example, and any other suitable reassignment algorithm or criteria may be used to assign a unique subcarrier or a unique subcarrier group to each channel, where each assigned subcarrier is used by only one of the DUT test channels in a given pass.

[0042] Figure 5 The illustrated subcarrier assignment groups include groups of adjacent subcarriers 501, 502, 503, and 504. Not all possible implementations require contiguity, and two different channels may be assigned more than one subcarrier that is adjacent to subcarriers assigned to different channels. For example, a set of assigned groups may be staggered such that each subcarrier assignment group has no adjacent subcarriers within the group.

[0043] Figure 6-9 The example shows that in the third pass, the four DUTs tested by the example are Figure 5 1-504 , the corresponding MATLAB code generated under the corresponding assigned unique subcarrier group examples 501-504 simulates the transceiver transmission test waveforms 600, 700, 800, and 900. In this example, the third test pass, the controller 150 has assigned the third subcarrier group 503 for testing the transceiver circuit 114 of the first test channel 111 (e.g., subcarriers 2, 3, 4, 5, 6, 8, 9, 10, 11, and 12), and the simulated waveform 600 shows the first group spectrum transmitted by the DUT of the first channel 111. In this third pass, the second test channel 121 has been assigned the fourth subcarrier group 504 (e.g., subcarriers 16, 17, 18, 19, 20, 22, 23, 24, 25, and 26), and the simulated waveforms 700 and Figure 7 The second group spectrum transmitted by the DUT of the second channel 121 is shown. The simulation waveform 800 and Figure 8 shows a third group spectrum transmitted by the DUT of the third channel 131, which has been assigned by the controller 150 with the first subcarrier group 501 (e.g., subcarriers -16, -17, -18, -19, -20, -22, -23, -24, -25, and -26), and Figure 9Waveform 900 in FIG. 5 shows a fourth group spectrum transmitted by the DUT of the fourth channel 141, which has been assigned the second subcarrier group 502 (e.g., subcarriers -2, -3, -4, -5, -6, -8, -9, -10, -11, and -12). Figure 10 A received composite OFDM signal 1000 is shown as received by a test instrument during a parallel transmission test of four DUTs. As shown in waveform 1000, the test instrument 102 receives the full spectrum from the RF combiner / splitter 104 and evaluates each assigned subcarrier individually. This facilitates highly parallel testing using a single test instrument 102 for concurrent RF testing without the expense and complexity associated with providing a separate test instrument for each DUT under test. The illustrated example synthesizes multiple virtual sub-data channels / carriers within a physical RF channel for use by a single, shared test instrument 102 using a modified OFDM implementation. In other examples, other frequency division multiplexing implementations are possible. Furthermore, as described above, the test system and method can be used with DUTs having an integrated or internal modem, or with DUTs without a modem, where the system includes a system modem to encode and decode OFDM signals at baseband, with each DUT using only a certain number of virtual subcarriers assigned by the controller 150. The DUT under test in the illustrated example uses a single shared system clock 109 (e.g., Figure 1 ) for synchronization, and the system may include adjustable delay capabilities between channels if helpful. Various examples facilitate sharing expensive test and measurement instruments (e.g., test instrument 102) for generating and analyzing OFDM signals, where a single shared spectrum analyzer can analyze all DUT transmit signals in parallel and report the received signal power and error vector magnitude (EVM) for each corresponding subcarrier.

[0044] The described systems and methods can be used to test any type of RF integrated circuit, including but not limited to Bluetooth and Wi-Fi microcontrollers (MCUs), that have RF transceivers, RF transmitters, RF receivers, or other RF circuitry to be tested in parallel with other DUTs. Furthermore, system and method examples can be used for parallel testing of different DUT types, for example, to test RF transceivers of different types of integrated circuits installed in corresponding channel sockets. The described examples can advantageously improve ATE testing and bench verification throughput, and reduce ATE testing costs and bench verification cycle times, facilitating faster time to market and cost-effective automated testing in manufacturing production. Various system implementations can include a load board structure designed to include or provide connections for an RF combiner / distributor module, as well as appropriate software on the test instrument to support per-subchannel reporting, analysis, and the like. Furthermore, portions of the described systems and methods can be incorporated into a test instrument, such as providing an OFDM-HPT modem within the test instrument 102, thereby creating a highly parallel test setup for DUTs that only have RF transceiver circuitry (e.g., RF front-end amplifiers). Furthermore, the described solution facilitates highly parallel test operations for many concurrently tested DUTs, e.g., where N can be as high as 48 in an example OFDM-HPT implementation, where smaller values ​​of N (e.g., 4, 8, etc.) still provide advantages with respect to cost savings, reduced test time, faster time to market, etc.

[0045] Modifications to the described examples are possible and other implementations are possible within the scope of the claims.

Claims

1. A testing system comprising: A test instrument having a signal terminal; a splitter having a splitter input connected to the signal terminal of the test instrument and an integer number N of splitter outputs, N being greater than 1; test channels, each test channel comprising a receptacle having receptacle terminals connected to a respective one of the splitter outputs to couple a transceiver terminal of a mounted electronic device under test (DUT) to the respective splitter output; as well as A controller is configured to operate the test instrument to concurrently test transceiver circuits of the installed DUTs under respective unique subcarriers of the OFDM signal at the signal terminals. 2 . The test system of claim 1 , wherein the controller is configured to operate a modem operably coupled to the transceiver circuit of each respective test channel.

3. The test system of claim 2, wherein the modem of each respective test channel is included in a respective DUT.

4. The test system of claim 2, wherein the modem of each respective test channel is external to the respective DUT.

5. The test system of claim 1 , wherein the controller is configured to: controlling individual DUTs to perform concurrent transmission on the corresponding unique subcarriers; controlling the test instrument to analyze individual signals of the corresponding unique subcarriers received at the signal terminal of the test instrument; and A transmission test result of each respective DUT is determined as a pass or fail based on a received carrier signal strength of the respective unique subcarrier received at the signal terminal of the test instrument and a magnitude of a decoded vector magnitude error parameter of the respective unique subcarrier received at the signal terminal of the test instrument.

6. The test system of claim 5, wherein the controller is configured to: controlling the test instrument to transmit concurrently on each of the corresponding unique subcarriers at the signal terminal; controlling the modem of each respective test channel to concurrently decode the received signal of the respective unique subcarrier and send the decoded data of each respective unique subcarrier to the controller; and A received test result for each respective DUT is determined to be a pass or fail based on the decoded data for each respective unique subcarrier.

7. The test system of claim 1 , wherein the controller is configured to: controlling the test instrument to transmit concurrently on each of the corresponding unique subcarriers at the signal terminal; controlling the modem of each respective test channel to concurrently decode the received signal of the respective unique subcarrier and send the decoded data of each respective unique subcarrier to the controller; and A received test result for each respective DUT is determined to be a pass or fail based on the decoded data for each respective unique subcarrier.

8. The test system of claim 1, wherein the controller is configured to operate the test instrument to concurrently test transceiver circuitry of the installed DUT under respective groups of the unique subcarriers of the OFDM signal at the signal terminals.

9. The test system of claim 1, wherein the controller is configured to operate the test instrument to perform multiple test passes using different assigned unique subcarriers for respective DUTs in each test pass.

10. The test system of claim 1, wherein the controller is configured to operate the test instrument to perform a single test pass using fewer than all of the unique subcarriers for a respective DUT.

11. A method of manufacturing an electronic device, the method comprising: installing the manufactured electronic devices in respective sockets, wherein the transceiver circuitry of each respective electronic device is connected to a respective splitter output of the splitter; A single test instrument is operated to concurrently test the transceiver circuits of installed electronic devices under respective unique subcarriers of an OFDM signal at a signal terminal of the test instrument.

12. The method of claim 11, further comprising operating a modem operably coupled to each respective transceiver circuit while concurrently testing the transceiver circuits of the installed electronic devices.

13. The method of claim 12, wherein the modem is included in the respective electronic device.

14. The method of claim 12, wherein the modem of each respective test channel is external to the respective electronic device.

15. The method according to claim 11, comprising: controlling individual electronic devices to perform concurrent transmission on the corresponding unique subcarrier; controlling the test instrument to analyze individual signals of the corresponding unique subcarriers received at the signal terminals of the test instrument; as well as A transmission test result of each respective electronic device is determined to be a pass or fail based on a received carrier signal strength of the respective unique subcarrier received at the signal terminal of the test instrument and a magnitude of a decoded vector magnitude error parameter of the respective unique subcarrier received at the signal terminal of the test instrument.

16. The method according to claim 15, comprising: controlling the test instrument to transmit concurrently on each of the corresponding unique subcarriers at the signal terminal; controlling the modem of each corresponding test channel to concurrently decode the received signal of the corresponding unique subcarrier; as well as A determination is made as to whether the received test result for each respective electronic device is a pass or fail based on the decoded data for each respective unique subcarrier.

17. The method according to claim 11, comprising: controlling the test instrument to transmit concurrently on each of the corresponding unique subcarriers at the signal terminal; controlling the modem of each respective test channel to concurrently decode the received signal of the respective unique subcarrier and send the decoded data of each respective unique subcarrier to the controller; as well as A received test result for each respective electronic device is determined to be a pass or fail based on the decoded data for each respective unique subcarrier.

18. The method of claim 11, comprising operating the test instrument to concurrently test transceiver circuitry of the installed electronic device under respective groups of the unique subcarriers of the OFDM signal at the signal terminals.

19. The method of claim 11, comprising operating the test instrument to perform multiple test passes using a different assigned unique subcarrier for the respective electronic device in each test pass.

20. The method of claim 11, comprising operating the test instrument to perform a single test pass using fewer than all of the unique subcarriers for the respective electronic devices.

Images