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Efficient Test Methods for RF Transceivers

<p>Advancements of the semiconductor technology opened a new era in</p>
<p>wireless communications which led manufacturers to produce faster,</p>
<p>more functional devices in much smaller sizes. However, testing</p>
<p>these devices of today's technology became much harder and expensive</p>
<p>due to the complexity of the devices and the high operating speeds.</p>
<p>Moreover, testing these devices becomes more important since decreasing</p>
<p>feature sizes increase the probability of parametric and catastrophic</p>
<p>faults because of the severe effects of process variations. Manufacturers</p>
<p>have to increase their test budgets to address quality and reliability</p>
<p>concerns. In the radio frequency (RF) domain, overall test cost are higher</p>
<p>due to equipment costs, test development and test time costs. Advanced</p>
<p>circuit integration, which integrates various analog and digital circuit</p>
<p>blocks into single device, increases test costs further because of the</p>
<p>additional tests requiring new test setups with extra test equipments.</p>
<p>Today's RF transceiver circuits contain many analog and digital circuit</p>
<p>blocks, such as synthesizers, data converters and the analog RF front-end</p>
<p>leading to a mixed signal device. Verification of the specifications and</p>
<p>functionality of each circuit block and the overall transceiver require</p>
<p>RF instrumentation and lengthy test routines. In this dissertation, we</p>
<p>propose efficient component and system level test methods for RF</p>
<p>transceivers which are low cost alternatives to traditional tests.</p>
<p>In the first component level test, we focus on in-band phase noise of the</p>
<p>phase locked loops (PLL). Most on-chip self-test methods for PLLs aim at</p>
<p>measuring the timing jitter that may require precise reference clocks and/or</p>
<p>additional computation of measured specs. We propose a built in test (BiT)</p>
<p>circuit to perform a go/no-go test for in-band PLL phase noise. The proposed</p>
<p>circuit measures the band-limited noise power at the input of the voltage</p>
<p>controlled oscillator (VCO). This noise power is translated as the high</p>
<p>frequency in-band phase noise at the output of the PLL. Our circuit contains</p>
<p>a self calibration sequence based on a simple sinusoidal input signal to make</p>
<p>it robust with respect to process variations.</p>
<p>The second component level test is a built in self test (BiST) scheme</p>
<p>proposed for analog to digital converters (ADC) based on a linear ramp</p>
<p>generator and efficient output analysis. The proposed analysis method is</p>
<p>an alternative to histogram based analysis techniques to provide test time</p>
<p>improvements, especially when the resources are scarce. In addition to the</p>
<p>measurement of differential nonlinearity (DNL) and integral nonlinearity</p>
<p>(INL), non-monotonic behavior of the ADC can also be detected with the</p>
<p>proposed technique. The proposed ramp generator has a high linearity</p>
<p>capable of testing 13-bit ADCs.</p>
<p>In the proposed system level test methods, we utilize the loop-back</p>
<p>configuration to eliminate the need for an RF instrument. The first loop-back</p>
<p>test method, which is proposed for wafer level test of direct conversion</p>
<p>transceivers, targets catastrophic and large parametric faults. The use of</p>
<p>intermediate frequencies (IF) generates a frequency offset between the transmit</p>
<p>and receive paths and prevents a direct loop-back connection. We overcome this</p>
<p>problem by expanding the signal bandwidth through saturating the receive path</p>
<p>composed of low noise amplifier (LNA) and mixer. Once the dynamic range of the</p>
<p>receiver path is determined, complete transceiver can be tested for catastrophic</p>
<p>signal path faults by observing the output signal. A frequency spectrum</p>
<p>envelope signature technique is proposed to detect large parametric faults.</p>
<p>The impact of impairments, such as transmitter receiver in-phase/quadrature</p>
<p>(I/Q) gain and phase mismatches on the performance have become severe due to</p>
<p>high operational speeds and continuous technology scaling. In the second system</p>
<p>level loop-back test method, we present BiST solutions for quadrature modulation</p>
<p>transceiver circuits with quadrature phase shift keying (QPSK) and Gaussian</p>
<p>minimum shift keying (GMSK) baseband modulation schemes. The BiST methods</p>
<p>use only transmitter and receiver baseband signals for test analysis. The</p>
<p>mapping between transmitter input signals and receiver output signals are</p>
<p>used to extract impairment and nonlinearity parameters separately with the</p>
<p>help of signal processing methods and detailed nonlinear system modeling.</p>
<p>The last system level test proposed in this dissertation combines the benefits </p>
<p>of loop-back and multi-site test approaches. In this test method, we present </p>
<p>a 2x-site test solution for RF transceivers. We perform all operations on </p>
<p>communication standard-compliant signal packets, thereby putting the device </p>
<p>under the normal operating conditions. The transmitter on one device under </p>
<p>test (DUT) is coupled with a receiver on another DUT to form a complete TX-RX </p>
<p>path. Parameters of the two devices are decoupled from one another by carefully </p>
<p>modeling the system into a known format and using signal processing techniques.</p> / Dissertation

Identiferoai:union.ndltd.org:DUKE/oai:dukespace.lib.duke.edu:10161/2400
Date January 2010
CreatorsErdogan, Erdem Serkan
ContributorsBrooke, Martin A, Ozev, Sule
Source SetsDuke University
Languageen_US
Detected LanguageEnglish
TypeDissertation
Format8339500 bytes, application/pdf

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