کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7929074 1512566 2015 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Hybrid direct-detection differential phase shift keying-multipulse pulse position modulation techniques for optical communication systems
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد مواد الکترونیکی، نوری و مغناطیسی
پیش نمایش صفحه اول مقاله
Hybrid direct-detection differential phase shift keying-multipulse pulse position modulation techniques for optical communication systems
چکیده انگلیسی
In this paper, a hybrid differential phase shift keying-multipulse pulse position modulation (DPSK-MPPM) technique is proposed in order to enhance the receiver sensitivity of optical communication systems. Both binary and quadrature formats are adopted in the proposed systems. Direct-detection DPSK schemes that are based on an asymmetric Mach-Zehnder interferometer with a novel ultrafast discrete delay unit are presented to simplify the receiver implementation. Expressions for the bit-error rate (BER) of the proposed hybrid modulation techniques are derived taking into account the effect of the optical amplifier noise. Under the constraints of the same transmitted data rate, bandwidth, and average received optical signal-to-noise ratio, the BER performances of the proposed schemes are then evaluated numerically and compared with that of traditional differential binary phase shift keying (DBPSK), differential quadrature phase shift keying (DQPSK), and MPPM schemes and with that of recent hybrid schemes. Furthermore, a comparison between the proposed systems and the traditional ones is held in terms of the bandwidth-utilization efficiency. Our results reveal that the proposed hybrid schemes are more energy-efficient and have higher receiver sensitivity compared with the traditional ones while improving the bandwidth-utilization efficiency. The proposed DPSK-MPPM system is ready to accommodate adjustable (or variable) bit rates, by virtue of the programmable delay integrated to the receiver system.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Optics Communications - Volume 357, 15 December 2015, Pages 86-94
نویسندگان
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