Analytical analysis of IF-penalties for different FSK and CPFSK detection schemes

We analyze the system performance of optical heterodyne CPFSK receivers with AFC loops. The effects of closed loop gain and postdetection filters are taken into account.The GQR (Gaussian quadrature rule) method is used to deal with the laser phase noise characteristics in computing the bit-error rates. The impact of closed loop gain on the system performance is investigated. The optimum design of postdetection filters is outlined in showing the improvement of system performance compared with the system without AFC.

Section: System Modelmentioning

confidence: 99%

System Performance of Optical Heterodyne CPFSK Receivers with AFCs

Hsu¹,

Wang²

2000

“…In writing (11) we have omitted the direct current components, In writing (11) we have omitted the direct current components,…”

Section: System Modelmentioning

confidence: 99%

Performance Analysis of Optical Receivers with Phase Diversity FSK Detection Scheme

Ho¹,

Wang²

1994

The performance of continue phase shift keying (CPFSK) optical communication system is investigated. The receiver recovers the phase of the optical signal by using a phase diversity technique. The system with delay-and-multiply frequency discriminator is examined. Exact mean and variance of output statistic are derived without assumption of small delay time in the delay-and-multiply discriminator. The results of Gaussian approximation are applied to finding the system bit error rate floors and the optimum delay times. It is found that for different linewidth the delay time should be set differently. The influences of laser linewidth, noise correlation, and filter bandwidth are taken into account. Results of computer simulation illustrate the non-Gaussian character of the probability density function of the receiver output current.

“…Optical communication systems using frequency shift keying (FSK) scheme can tolerate laser phase noise if the laser linewidth to frequency deviation ratio is kept low enough [1]. When the laser phase noise is ignored, FSK systems have higher 3 dB sensitivity than systems with amplitude shift keying (ASK) [2].…”

Section: Introductionmentioning

confidence: 99%

Performance Analysis of Optical CPFSK Receivers with Gaussian Frequency Pulse Shape

Ho¹,

Wang²

1995

The performance of an optical CPFSK receiver can be improved by choosing adequate shape of Gaussian frequency pulse and the delay time of the delayand-multiply frequency discriminator. Exact mean and variance of the output statistic are derived. The results of Gaussian approximation are applied to finding the system bit error rate floors and the optimum delay times. For various Gaussian frequency pulse shapes, the delay times should be set accordingly. The effects of laser linewidth and shot noise are taken into account.