scholarly journals Performance Analysis, Characteristics, and Simulation of Digital QAM

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Nikolaos Voudoukis
Keyword(s):  
Performance Analysis ◽  
Bit Error Rate ◽  
Error Rate ◽  
Amplitude Modulation ◽  
Performance Indicators ◽  
Digital Transmission ◽  
Quadrature Amplitude Modulation ◽  
Radio Communications ◽  
Awgn Channel ◽  
Data Rates

Quadrature Amplitude Modulation or QAM is a form of modulation which is widely used for modulating data signals onto a carrier used for radio communications. QAM, when used for digital transmission for radio communications applications is able to carry higher data rates than ordinary amplitude modulated schemes and phase modulated schemes. This paper presents the various fields where QAM can be implemented, describes modulator/demodulator block diagrams for transmitters as well as receivers, provides an introduction of certain performance indicators of modulation and a list of applications using alternative implementations of QAM. Also the paper presents a simulation of QAM using Simulink (example of 16-QAM signal) with signal trajectors and constellation plots. It is compared the theoretical and simulated Bit Error Rate (BER) for 16-QAM with Gray coding in an AWGN channel. Some general conclusions are also cited.

scholarly journals Performance analysis of carrier depletion silicon PIN phase shifter

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Jesuwanth Sugesh Ramesh Gabriel ◽  
Sivasubramanian Arunagiri
Keyword(s):  
Performance Analysis ◽  
Bit Error Rate ◽  
Error Rate ◽  
Phase Shifter ◽  
Extinction Ratio ◽  
Fibre Length ◽  
Data Rate ◽  
Operating Voltage ◽  
Data Centre ◽  
Mach Zehnder Modulator

AbstractIn this paper, we report the performance of a carrier depletion Silicon PIN phase shifter with over layer of 130 nm. It is observed that an optimum intrinsic gap of 250 nm for a device length of 5 mm at 2 V, resulted in Extinction Ratio (ER) of 23.41 dB and Bit Error Rate (BER) of 1.00 × 10−7 is obtained for 50 Gbps. The phase shifter is also designed for length 2 mm with an intrinsic gap of 100 nm at an operating voltage <4 V. The study also reveals that the proposed design for Mach-Zehnder modulator operating at a data rate of 100 Gbps for the concentration of P = 7 × 1017 cm−3 and N = 5 × 1017 cm−3 gives better BER and phase performance. The proposed design was also analysed in an intra-data centre communication setup of fibre length 15 km.

Terrestrial Free Space Optic Propagation Analysis Considering Malaysia Weather Condition

2012 ◽  
Author(s):  
Wan Rizal Hazman Wan Ruslan ◽  
Sevia Mahdaliza Idrus ◽  
Arnidza Ramli ◽  
Norhafizah Ramli ◽  
Abu Sahmah Mohd Supa’at ◽  
...  
Keyword(s):  
Bit Error Rate ◽  
Error Rate ◽  
Free Space ◽  
Weather Condition ◽  
Q Factor ◽  
Performance Characterization ◽  
Space Optics ◽  
Terrestrial System ◽  
Data Rates ◽  
Free Space Optic

Pemantulan cahaya matahari oleh cermin atau dikenali sebagai heliograf adalah kaedah awal komunikasi optik wayarles (OWC). Sewajarnya, sistem komunikasi moden mendedahkan kadar data yang tinggi di samping kualiti perkhidmatan yang lebih baik berbanding kaedah terdahulu. Sistem komunikasi optic wayarles mempunyai banyak kebaikan dimana ia adalah penting untuk sistem daratan, sebagai contoh penggunaan Optik Ruang Bebas (FSO) di kawasan luar. Di dalam kertas kerja ini, gambaran dan pencirian prestasi sistem Optik Ruang Bebas seperti pelemahan, kadar bit kesalahan (BER), faktor Q dan jenis pengesan yang berguna untuk pengesanan dalam sistem FSO dibentangkan. Sistem telah direkabentuk dan disimulasi untuk perincian prestasi dengan mengambil kira kawasan Subang. Kata kunci: Pelemahan; kadar bit kesalahan; pengesan foto; faktor Q; sistem daratan The reflection of sunlight by mirrors or known as the heliograph is an early method of optical wireless communication (OWC). Naturally, modern communication system reveals much higher data rates with better quality of service (QoS) compared to those ancient methods. There are many advantages of OWC which are important for a terrestrial system for example the usage of an outdoor free space optics (FSO) system. In this paper, a description and system performance characterization of the FSO such as attenuation, bit error rate (BER), Q factor and the type of detectors that are highly useful for detection in FSO systems are presented. The system are designed and simulated for performance characterization considering Subang terrestrial. Key words: bit error rate; photodetector; Q factor; terrestrial system

Sign in / Sign up

Export Citation Format

Share Document