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Effects of Phase Noise on OFDM Systems With and Without PLL: Characterization and Compensation
"... Abstract—In this paper, we propose an algorithm for suppressing intercarrier interference due to phase noise in coded orthogonal frequency division multiplexing (OFDM) systems. The algorithm approximates the phasenoise waveform by using a Fourier series approximation for the current phasenoise rea ..."
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Cited by 32 (1 self)
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Abstract—In this paper, we propose an algorithm for suppressing intercarrier interference due to phase noise in coded orthogonal frequency division multiplexing (OFDM) systems. The algorithm approximates the phasenoise waveform by using a Fourier series approximation for the current phasenoise realization. Thereby, it cancels the effects of the phase noise beyond the standard common phase error correction used in contemporary OFDM standards. The algorithm requires that the correlation properties of the intercarrier interference are known. We calculate these properties in terms of the phasenoise spectral correlation matrix for both Wiener and Ornstein–Uhlenbeck phasenoise models, respectively. This modeling corresponds to a freerunning oscillator, as well as a phaselocked loop realization of the local oscillator in orthogonal frequency division multiplexing transceivers. For both transceiver configurations, we investigate the performance of the proposed algorithm. It is demonstrated that the new algorithm achieves as much as one order of magnitude better performance in terms of packet/bit error rate when compared to a receiver with only the common phase error suppression. Index Terms—Orthogonal frequency division multiplexing (OFDM), phaselocked loop, phase noise. I.
Analysis of Jitter in PhaseLocked Loops
 IEEE Transactions on Circuits and Systems
, 2002
"... Abstract—Jitter in clock signals is analyzed, linking noise in freerunning oscillators to shortterm and longterm timedomain behavior of phaselocked loops. Particular attention is given to comparing the impact of 1 noise and white noise in oscillators and frequency dividers on jitter in phaselo ..."
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Cited by 20 (0 self)
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Abstract—Jitter in clock signals is analyzed, linking noise in freerunning oscillators to shortterm and longterm timedomain behavior of phaselocked loops. Particular attention is given to comparing the impact of 1 noise and white noise in oscillators and frequency dividers on jitter in phaselocked loops of firstand secondorder. Theoretical analysis is supported by results obtained using mixedsignal behavior simulation. Index Terms—1 noise, frequency dividers, jitter, oscillators, phase noise, phaselocked loops (PLLs), white noise. I.
Performance Degradation of CodedOFDM due to Phase Noise
 in Proc. IEEE VTC
, 2003
"... In this paper we investigate the effect of phase noise on coded OFDM transmission with parameters typical for present OFDM based WLAN standards. Two different scenarios are compared, namely when the local oscillator at the receiver is realized as a free running oscillator or as a PLL. System perform ..."
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Cited by 7 (2 self)
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In this paper we investigate the effect of phase noise on coded OFDM transmission with parameters typical for present OFDM based WLAN standards. Two different scenarios are compared, namely when the local oscillator at the receiver is realized as a free running oscillator or as a PLL. System performance is evaluated as a degradation of the effective SINR, using BER simulations and in terms of achievable cutoff rate for different MQAM OFDM schemes in the presence of the phase noise.
Properties of Intercarrier Interference due to Phase Noise
 in OFDM,” Proc. IEEE ICC’05, Seoul, Korea
, 2005
"... Abstract — We present a unified analysis of intercarrier interference (ICI) which is caused by phase noise in OFDM. The ”small ” phase noise approximation known from the literature is dropped and analysis applies to a general phase noise model. The power of intercarrier interference is calculated in ..."
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Cited by 7 (2 self)
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Abstract — We present a unified analysis of intercarrier interference (ICI) which is caused by phase noise in OFDM. The ”small ” phase noise approximation known from the literature is dropped and analysis applies to a general phase noise model. The power of intercarrier interference is calculated in two ways, namely using an integral form and using an ICI correlation matrix which we also derive. As two special cases, the Wiener and OrnsteinUhlenbeck phase noise models, which are typical for freerunning and PLL synthesizer realizations of the local oscillator, respectively, are presented. Closed form expressions of the respective powers are calculated. We show that these theoretical considerations fit well to numerical experiments. The calculated ICI distribution show that ICI cannot be approximated by a gaussian random variable for a wide range of phase noise strengths contradicting the usual assumptions on the noise.
Numerical Performance Evaluation for OFDM Systems affected by Phase Noise and Channel Estimation Errors
"... In this paper we present a numerical approach to evaluate the bit error rate (BER) and mutual information of OFDM links subject to phase noise, channel estimation error and frequency selective fading channels. Based on the analytical modeling of the correlation between channel estimates and receive ..."
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Cited by 6 (0 self)
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In this paper we present a numerical approach to evaluate the bit error rate (BER) and mutual information of OFDM links subject to phase noise, channel estimation error and frequency selective fading channels. Based on the analytical modeling of the correlation between channel estimates and received signals affected by phase noise, the statistical properties of the received signal can be numerically evaluated by means of a probability density function. The results illustrate that our analysis can approximate the simulative performance very accurately if the power delay profile of the fading channels and the phase noise properties are known. Hence, we present a useful numerical tool for OFDM performance analysis under the presence of phase noise that can be used for planning and design of mobile device architectures, without running extensive simulations.
Investigation of a novel optical phase demodulator based on sampling phaselocked loop
 in Proc. IEEE Int. Topical Meeting Microw. Photon
, 2006
"... Abstract—A novel phaselocked coherent demodulator, based on a sampling phaselocked loop, is presented and investigated theoretically. The demodulator is capable of operating at high frequencies, by using optical sampling to downconvert the highfrequency input radiofrequency signal to the frequ ..."
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Cited by 5 (5 self)
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Abstract—A novel phaselocked coherent demodulator, based on a sampling phaselocked loop, is presented and investigated theoretically. The demodulator is capable of operating at high frequencies, by using optical sampling to downconvert the highfrequency input radiofrequency signal to the frequency range of the baseband loop. We develop a detailed theoretical model of the (sampling) phaselocked coherent demodulator and perform detailed numerical simulations. The simulation results show that the operation of the sampling demodulator resembles the operation of the baseband demodulator for very short optical pulses (<2 ps). Furthermore, we investigate how the signaltonoise ratio of the demodulator is affected by timing and amplitude jitter of the pulsed optical source. Index Terms—Analog links, coherent, microwave photonics, modulators, phaselocked loop (PLL), phasemodulation, sampling. I.
Steadystate analysis of voltage and current controlled oscillators
 ICCAD 2005
, 2005
"... Abstract — This paper introduces the problem of finding the steadystate and the numerical value of the controlling voltage or current for oscillators where the frequency of oscillation is known beforehand. These situations are very common when the oscillator is part of a phaselocked loop (PLL). In ..."
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Cited by 4 (2 self)
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Abstract — This paper introduces the problem of finding the steadystate and the numerical value of the controlling voltage or current for oscillators where the frequency of oscillation is known beforehand. These situations are very common when the oscillator is part of a phaselocked loop (PLL). In PLLs, the reference frequency as well as the divide ratios are known at the time of design. Therefore the desired frequency of the voltage (current) controlled oscillator is known but not the controlling voltage (current). We formulate this problem as the solution of an appropriate nonlinear equation. We present robust and efficient numerical techniques for solving this nonlinear equation both in time and frequency domain. We demonstrate using experimental results that this technique is at par with classical methods of calculating oscillator steadystate and period of oscillation for a given control voltage. We show that compared to a searchbased approach to calculating the desired control voltage or current, our direct method is a order of magnitude faster for the same accuracy. I.
On the System Level Prediction of Joint Time Frequency Spreading Systems with Carrier Phase Noise (†)
, 2010
"... Abstract Phase noise is a topic of theoretical and practical interest in electronic circuits. Although progress has been made in the characterization of its description, there are still considerable gaps in its effects especially on multicarrier spreading systems. In this paper, we investigate t ..."
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Abstract Phase noise is a topic of theoretical and practical interest in electronic circuits. Although progress has been made in the characterization of its description, there are still considerable gaps in its effects especially on multicarrier spreading systems. In this paper, we investigate the impact of a local oscillator phase noise on the multicarrier 2 dimensional (2D) spreading systems based on a combination of orthogonal frequency division multiplexing (OFDM) and code division multiple access (CDMA) and known as OFDMCDMA. The contribution of this paper is multifold. First, we use some properties of random matrix and free probability theory to give a simplified expression of signal to interference and noise ratio (SINR) obtained after equalization and despreading. This expression is independent of the actual value of the spreading codes and depends mainly on the complex amplitudes of estimated channel coefficients. Secondly, we use this expression to derive new weighting functions which are very interesting for the radio frequency (RF) engineers when they design the frequency synthesizer. Therefore, based on these asymptotic results, we adapt a new method to predict the bit error rate (BER) at the output of the channel decoder by using an effective SINR value. We show by simulations the validity of our models and that at a given BER, the required signal to noise ratio (SNR) may easily increase due to the carrier phase noise. Index Terms Multicarrier spreading systems, large system analysis, phase noise, SINR, EESM. I.
Ieee 802.11n mimoprototyping with dirty rf using the hardwareintheloop approach
 in Proc. of the 14th European Signal Processing Conference (EUSIPCO
, 2006
"... Modern wireless systems employ highly integrated hardware. Especially for the processing at radio frequencies, this high integration causes many undesired effects of signal distortion and degradation that must be simulated comprehensively before finalizing the system design. However, often the model ..."
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Cited by 2 (0 self)
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Modern wireless systems employ highly integrated hardware. Especially for the processing at radio frequencies, this high integration causes many undesired effects of signal distortion and degradation that must be simulated comprehensively before finalizing the system design. However, often the model accuracy is not sufficient to obtain sound results of the simulations; and in the case of sufficiently accurate models the simulation times get immense. A way out is to use real radio frequency hardware and digital physical layer simulations together in a hardwareintheloop system. Short simulation times and realworld radio characteristics are the unbeatable advantage of the hardwareintheloop approach. 1.
DiscreteTime, Linear Periodically TimeVariant PhaseLocked Loop Model for Jitter Analysis
"... Abstract—Timing jitter is one of the most significant phaselocked loop (PLL) characteristics, which directly affects the performance of the system in which the PLL is used. It is, therefore, important to develop the tools necessary to study and predict PLL jitter performance at design time. In this ..."
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Abstract—Timing jitter is one of the most significant phaselocked loop (PLL) characteristics, which directly affects the performance of the system in which the PLL is used. It is, therefore, important to develop the tools necessary to study and predict PLL jitter performance at design time. In this paper a discretetime, linear, periodically timevariant integer PLL model for jitter analysis is proposed, which accounts for the periodically timevarying effect of noise injected into the loop at various PLL components, such as VCO, charge pump, VCO buffer, VCO control node, and divider. The model also predicts the aliasing of jitter due to the downsampling and upsampling of thejittersignalaroundthePLLloop.Closedformexpressionsare derived for the output jitter spectrum and match well with results of eventdriven simulations of a thirdorder PLL. Index Terms—Cyclostationary analysis, discrete time analysis, impulse sensitivity function, jitter, modeling, noise, phase jitter, phase locked loops (PLL), phase noise, timing jitter. I.