The proliferation of wireless communication devices in the recent past has increased the pressure on semiconductor manufacturers to produce quality radio frequency (RF) modules and systems at a low cost. This entails reducing their test cost as well, since the cost of testing modern RF devices can be up to 40% of their manufacturing cost. The high test cost of these devices can be mainly attributed to (a) the expensive nature of the RF automated test equipment (ATE) used to perform wafer-level and fully packaged RF functionality tests, (b) limited test point access for the application and capture of test signals, (c) the long test development and application times, and (d) the lack of diagnostic tools to evaluate and improve the performance of loadboards and test resources in high-volume tests. In this thesis, a framework for the efficient production testing of high-performance RF modules and systems using low-cost ATE is presented. This framework uses low-speed, low-resolution test resources to generate reliable tests for complex RF systems. Also, the test resources will be evaluated and improved ahead of high-volume tests to improve test yield and throughput. The components of the proposed framework are: (1) Genetic ATPG for reliable test stimulus generation using low-resolution test resources: A genetic algorithm (GA) based automatic test pattern generator (ATPG) to optimize the alternate test stimulus for reliable testing of complex RF systems using low-resolution, low-cost test resources. These test resources may be on-chip or off-chip. (2) Concurrent voltage/current alternate test methodology: A testing framework for efficiently testing the high-frequency specifications of RF systems using low-frequency spectral and/or transient current signatures. Suitable on-chip and/or off-chip design-for-test (DfT) resources are used to enable the source and capture operations at lower frequencies. (3) Loadboard checker: A checker tool to accurately characterize/diagnose the DfT resources on the RF loadboards used to enable test of RF devices/systems using low-cost ATE. (4) Advanced test signal processing algorithms: The performance of the low-cost ATE resources, in terms of their linearity/resolution, will be evaluated and improved to enable the accurate capture of the test response signals.

The advent of deep submicron technology coupled with ever increasing demands from the customer for more functionality on a compact silicon real estate has led to a proliferation of highly complex integrated RF system-on-chip (SoC) and system-on-insulator (SoI) solutions. The use of scaled CMOS technologies for high frequency wireless applications is posing daunting technological challenges both in design and manufacturing test. To ensure market success, manufacturers need to ensure the quality of these advanced RF devices by subjecting them to a conventional set of production test routines that are both time consuming and expensive. Typically the devices are tested for parametric specifications such as gain, linearity metrics, quadrature mismatches, phase noise, noise figure (NF) and end-to-end system level specifications such as EVM (error vector magnitude), BER (bit-error-rate) etc. Due to the reduced visibility imposed by high levels of integration, testing for parametric specifications are becoming more and more complex. To offset the yield loss resulting from process variability effects and reliability issues in RF circuits, the use of self-healing/self-tuning mechanisms will be imperative. Such self-healing is typically implemented as a test/self-test and self-tune procedure and is applied post-manufacture. To enable this, simple test routines that can accurately diagnose complex performance parameters of the RF circuits need to be developed first. After diagnosing the performance of a complex RF system appropriate compensation techniques need to be developed to increase or restore the system performance. Moreover, the test, diagnosis and compensation approach should be low-cost with minimal hardware and software overhead to ensure that the final product is economically viable for the manufacturer. The main components of the thesis are as follows: 1) Low-cost specification testing of advanced radio frequency front-ends: Methodologies are developed to address the issue of test cost and test time associated with conventional production testing of advanced RF front-ends. The developed methodologies are amenable for performing self healing of RF SoCs. Test generation algorithms are developed to perform alternate test stimulus generation that includes the artifacts of test signal path such as response capture accuracy, load-board DfT etc. A novel cross loop-back methodology is developed to perform low cost system level specification testing of multi-band RF transceivers. A novel low-cost EVM testing approach is developed for production testing of wireless 802.11 OFDM front-ends. A signal transformation based model extraction technique is developed to compute multiple RF system level specifications of wireless front-ends from a single data capture. The developed techniques are low-cost and facilitate a reduction in the overall contribution of test cost towards the manufacturing cost of advanced wireless products. 2)Analog tuning methodologies for compensating wireless RF front ends: Methodologies for performing low-cost self tuning of multiple impairments of wireless RF devices are developed. This research considers for the first time, multiple analog tuning parameters of a complete RF transceiver system (transmitter and receiver) for tuning purposes. The developed techniques are demonstrated on hardware components and behavioral models to improve the overall yield of integrated RF SoCs.

[ES] En los últimos años han proliferado los nuevos sistemas de satélites, sobre todo las grandes constelaciones en las órbitas terrestres bajas. Casi todos los satélites transmiten señales digitales con diversas modulaciones y niveles de potencia. Y no sólo eso, el modelo de negocio exige un rápido despliegue de los satélites, lo que impone enormes restricciones a los proveedores de equipos de carga útil de microondas. Un área de riesgo clave para estos equipos sigue siendo la avería del multipactor bajo niveles de potencia de moderados a altos. Debido a la aleatoriedad inherente al fenómeno multipactor, los clientes tienden a añadir márgenes de diseño adicionales para los componentes de microondas de alta potencia. Esto se traduce en costes más elevados, dispositivos más voluminosos y más tiempo para las pruebas. A partir de la experiencia personal realizando ensayos de multipactor, la principal motivación del trabajo descrito en la tesis ha sido emprender una revisión exhaustiva de este fenómeno y desarrollar capacidades de ensayo multipactor de vanguardia. Proporcionar medios para la prueba rápida de multipactores bajo una variedad de señales moduladas de banda ancha. La tesis demuestra que las modulaciones analógicas y digitales tienen un impacto significativo en el umbral multipactor. También se analizan los regímenes multipactor a corto y largo plazo, regímenes que, en algunos casos, presentan umbrales multipactor muy diferentes para el mismo hueco crítico. La necesidad de reducir el peso de la carga útil de microondas convierte a la multiportadora en una excelente opción para los diseñadores. Al encaminar varias señales a través del mismo dispositivo, el peso de la carga útil se reduce drásticamente. Las soluciones comerciales para pruebas multicarrier no son adecuadas debido a los altos niveles de potencia requeridos. Se presentan varias estrategias para implementar bancos de pruebas multiportadora con parámetros controlables. Los resultados demuestran que la señal generada es precisa y estable en el tiempo. Por último, se propone un novedoso sistema de detección de multipactores para hacer frente a la detección de multipactores cuando se utilizan señales moduladas y multiportadora de cualquier ancho de banda. Este método tiene la misma sensibilidad que el conocido anulador de microondas para señales de onda continua y la supera para señales moduladas. El procesamiento digital de señales utilizado para detectar los patrones multipactor proporciona un método de detección totalmente autónomo. / [CA] En els darrers anys han proliferat els nous sistemes de satèl·lits, sobretot les grans constel·lacions a les òrbites terrestres baixes. Gairebé tots els satèl·lits transmetten dades digitals amb diverses modulacions i nivells de potència. I no només això, el model de negoci exigeix un ràpid desplegament dels satèl·lits, cosa que imposa enormes restriccions als proveïdors de càrrega útil de microones. Una àrea de risc clau per a aquests equips continua sent la descarrega de multipactor sota nivells de potència de moderats a alts. A causa de l'aleatorietat inherent al fenomen multipactor, els clients tendeixen a afegir marges de disseny addicionals per als components de microones d'alta potència. Això es tradueix en costos més elevats, dispositius més voluminosos i més temps per a les proves. A partir de l'experiència personal realitzant assajos de multipactor, la motivació principal del treball descrit a la tesi ha estat emprendre una revisió exhaustiva d'aquest fenomen i desenvolupar capacitats d'assaig multipactor d'avantguarda. Proporcionar mitjans per a la prova ràpida de multipactors sota una varietat de senyals modulats de banda ampla. La tesi demostra que les modulacions analògiques i digitals tenen un impacte significatiu al llindar multipactor. També s'analitzen els règims multipactor a curt i llarg termini, règims que, en alguns casos, presenten llindars multipactor molt diferents per al buit crític mateix. La necessitat de reduir el pes de la càrrega útil de microones fa de la transmissií multiportadora en una excel·lent opció per als dissenyadors. Encaminant diverses senyals a través del mateix dispositiu, el pes de la càrrega útil es redueix dràsticament. Les solucions comercials per a proves multicarrier no són adequades a causa dels alts nivells de potència requerits. Es presenten diverses estratègies per implementar bancs de proves multiportadora amb paràmetres controlables. Els resultats demostren que el senyal amb què s'alimenta el dispositiu sotmès a proves és precís i estable en el temps. Finalment, es proposa un nou sistema de detecció de multipactors per fer front a la detecció de multipactors quan s'utilitzen senyals modulats i multiportadors de qualsevol amplada de banda. Aquest mètode té la mateixa sensibilitat que el conegut anul·lador de microones per a senyals d'ona contínua i la supera per a senyals modulats. El processament digital de senyals utilitzat per detectar els patrons multiactor proporciona un mètode de detecció totalment autònom. / [EN] In the recent past, there has been a proliferation of new satellite systems, especially the large constellations in the Low Earth Orbits (LEOs). Nearly all satellites now carry digital traffic with a variety of modulations and power levels. Not only that, the business model requires rapid deployment of satellites, putting enormous constraints for the suppliers of microwave payload hardware. A key risk area for such equipment remains the multipactor breakdown under moderate to high power levels. Owing to the inherent randomness of the multipactor phenomenon, customers tend to add extra design margins for the high power microwave components. This results in higher costs, bulkier devices and longer time for testing. Based on personal experience in multipactor testing, the prime motivator for the work described in the thesis has been to undertake a comprehensive review of this phenomenon and develop cutting edge multipactor test capabilities, providing means for the rapid multipactor testing under a variety of wide-band modulated signals. The thesis dissertation shows that analog and digital modulations have a significant impact in the multipactor threshold. The short and long-term multipactor regimes are also analyzed, regimes that, in some cases, have very different multipactor thresholds for the same critical gap. The need to reduce the microwave payload weight by using multicarriers in a single transponder provides an excellent option for designers. By routing several signals through the same device, the payload weight is dramatically reduced. Commercial solutions for multicarrier testing are not suitable because of the high power levels required. Several strategies to implement multipactor test benches with controllable parameters are presented. Results prove that the signal being fed to the device under tests is accurate and stable over time. Finally, a novel multipactor detection system is proposed to cope with multipactor detection when modulated and multicarrier signals of any bandwidth are used. This method has the same sensitivity as the well known microwave nulling for continuous wave signals and surpasses it for modulated signals. The digital signal processing used to detect the multipactor patterns provides a full autonomous detection method. / Monerris Belda, Ó. (2023). Advanced Techniques for Multipactor Testing [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/192786