PIN Receiver Research Articles

Efficient employment of VCSEL light sources in high speed dispersion compensation system

Abstract This paper demonstrated the efficient employment of vertical cavity surface emitting laser (VCSEL) light sources in high speed dispersion compensation systems. VCSEL are compared with CW laser and distributed feedback laser in the modulated light output power, signal quality factor and minimum data error rates through the fiber system. Light signal base band modulated power is clarified with spectral frequencies after LiNb MZ modulators. Light signal base band modulated amplitude is simulated against base band time frequencies after LiNb MZ modulators. The total light signal index base band modulated power/amplitude value is estimated after LiNb MZ modulators for various light sources. The light signal base band modulated power is demonstrated with both spectral frequencies and time interval after fiber loop control length with compensation system. Total light signal index base band modulated power/amplitude value is estimated numerically after fiber loop control length with compensation system. The modulated electronic signal base band modulated power is indicated with spectral frequencies after PIN receiver. The light signal base band modulated amplitude is studied clearly against base band time frequencies after PIN receiver. The signal quality factor, BER, and modulated lighted output power are clarified and sketched against fiber system lengths for various light sources.

Two-Stage Link Loss Optimization of Divergent Gaussian Beams for Narrow Field-of-View Receivers in Line-of-Sight Indoor Downlink Optical Wireless Communication (Invited)

The predominant focus of research in high-speed optical wireless communication (OWC) lies in line-of-sight (LOS) links with narrow infrared beams. However, the implementation of precise tracking and steering necessitates delicate active devices, thereby presenting a formidable challenge in establishing a cost-effective wireless transmission. Other than using none-line-of-sight (NLOS) links with excessive link losses and multi-path distortions, the simplification of the tracking and steering process can be alternatively achieved through the utilization of divergent optical beams in LOS. This paper addresses the issue by relaxing the stringent link budget associated with divergent Gaussian-shaped optical beams and narrow field-of-view (FOV) receivers in LOS OWC through the independent optimization of geometrical path loss and fiber coupling loss. More importantly, the geometrical path loss is effectively mitigated by modifying the transverse intensity distribution of the optical beam using manipulations of multi-mode fibers (MMFs) in an all-fiber configuration. In addition, the sufficiently excited higher order modes (HOMs) of MMFs enable a homogenized distribution of received optical powers (ROPs) within the coverage area, which facilitates the mobility of end-users. Comparative analysis against back-to-back links without free-space transmission demonstrates the proposed scheme’s ability to achieve low power penalties. With the minimized link losses, experimental results demonstrate a 10 Gbps error-free (BER < 10−13) LOS OWC downlink transmission at 2.5 m over an angular range of 10° × 10° without using any optical pre-amplifications at a typical PIN receiver. The proposed scheme provides a simple and low-cost solution for high-speed and short-range indoor wireless applications.

On off keying line coding based optical transmitter for various both optical fiber communication and OWC channels

Abstract This paper demonstrated the on off keying line based optical line transmitter for different fiber communication and wireless lighted channels. The max Q form and min BER values after PIN receiver based optical fiber base band channel, linear multi-mode fiber channel and OWC at optimum length is clarified. Lighted power variations after light fiber channel, linear multi-mode fiber channel and OWC versus spectral base band wavelength variations at optimum length is demonstrated. Lighted power form variations after lighted base band fiber channel, linear multi-mode fiber channel and OWC versus time variations at optimum length is indicated. Total lighted power after optical fiber base band channel, linear multi-mode fiber channel and OWC at optimum length is clarified. Total electrical power after PIN receiver based optical fiber channel, linear multi-mode fiber channel and OWC at optimum length.

Bipolar alternate mark inversion encoding (BAMI) scheme for performance signature of optical transceiver systems under thermal effects

Abstract This study has clarified the bipolar alternate mark inversion encoding scheme for performance signature of optical transceiver systems under thermal effects. The light power through optical fiber channel variations with spectral wavelength at various temperature variations are clarified. The total electrical power through PIN receiver at various temperature variations are demonstrated. The electrical power amplitude, max Q Factor and min BER through PIN receiver at different temperature variations are clarified in details. Electrical and optical signal per noise ratio with laser bias current at various ambient temperatures are demonstrated. The total optical/electrical power and maximum quality signal with laser bias current at various temperature variations.

Optimization of the performance parameters of the Giga passive optical networks for high transmission data rates with various modulation schemes

Abstract This article has demonstrated the performance parameters optimization of the Giga passive optical networks (PONs) can enhanced with high transmission data rates with various modulation schemes. These modulation schemes are Mach–Zehnder modulator (MZM), electroabsorption modulator (EAM), amplitude modulator (AM), dual drive MZM measured (DDMZMM), electroabsorption modulator measured (EAMM), and LiNb MZM. The network reach can be extended to 30 km with 20 Gb/s. Maxi Q and mini bit error rate can be measured at both PIN and APD receivers. The study has emphasized AM modulation scheme is the best candidate modulation scheme for upgrading the network performance efficiency. LiNb MZM is the worst modulation scheme for the estimation of PONs performance. Optical power signals after fiber optic channel based different modulation schemes are clarified. EAM modulation scheme is the best technique for upgrading optical power signal through the network reach.

Evaluation and experimental comparisons of different photodetector receivers for visible light communication systems under typical scenarios

Positive-intrinsic-negative diode (PIN), avalanche photodiode (APD), and single photon avalanche diode (SPAD) are commonly used optoelectronic receivers with different characteristics in practical visible light communication system. To determine the most appropriate candidate, different signal and ambient light strength in the communication scenarios should be taken into account. APD and SPAD receivers have higher sensitivities than PIN, but there are still some defects that restrain their operation performance. APD receiver may generate excessive shot noise, whereas SPAD is limited by the dead time, afterpulsing, and smaller detection area. We initially analyze the noise characteristics of PIN, APD, and SPAD receivers. SNR models are established, and the main factors affecting the performance of APD and SPAD receivers are concluded. Then, the comparison experiments of three kinds of receivers in various transmission distances are conducted, respectively. Finally, the experimental results show that: short and mid distance conditions, PIN and APD are better choices, whereas SPAD performs better in long-distance communication. In addition, if a certain intensity of ambient light is introduced, APD is still better than SPAD even in long distance.

Comparison of single-lane 100 Gb/s PAM-4 and DB-PAM-4 signals transmission based on 12G receiver with FFE and LDPC

Using low-bandwidth receivers to transmit single-wavelength 100 Gb/s data provides a low-cost and high-rate solution for the next generation passive optical networks (PONs). In this paper, we experimentally investigate the transmission of single-wavelength 100 Gb/s four-level pulse–amplitude modulation (PAM-4) and duobinary PAM-4 (DB-PAM-4) signal with a cost-effective 12 GHz PIN receiver. Feed-forward equalization (FFE) in conjunction with low-density parity-check (LDPC) is applied to enhance the bit error rate (BER) performance of the 25-km standard single-mode fiber (SSMF) transmitted signal. The Max-Log-maximum a posteriori (MAP) algorithm is utilized to computing soft information and provide it to LDPC decoding. As a result, under the same limited-bandwidth transmission conditions, DB-PAM-4 shows superior performance compared to PAM-4, reducing BER below the LDPC threshold 10−2. Error-free 25 km-transmission of 100 Gb/s DB-PAM-4 signal is realized employing 35-tap FFE and LDPC. On the contrast, the BER of PAM-4 cannot even be lower than 10−1, even with more taps and longer training sequences.

Fire Mechanism in Power Connection Points of Outlets and Suggestion of a New Identification Method

Most outlet fires occur around plug pins and plug pin receivers. However, no research has been conducted on ignitions at power connection points. This study confirms the possibility of ignition after incomplete connection, using a stranded wire, to the power connection point of an outlet. The experiment was divided into basic and reproducing experiments. The basic experiment confirmed the possibility of ignition according to the number of wire strands connected to the power connection point, and it identified the characteristics of the residue after the fire. In the reproducing experiment, lamps, vacuum cleaners, and heaters were connected to an outlet to check if the ignition at the connection advanced into a fire. The fire advanced due to the heat and arc generated at the connection point, and partial losses were identified in the U-type holder and clip. Accordingly, the results demonstrate that a fire may occur when the stranded wire is incompletely connected to the outlet. Moreover, it was confirmed that the cause of a fire can be determined based on the characteristics of the residue.

Investigation of Different Modulation Formats for Extended Reach NG-PON2 using RSOA

Global market forecasts predicted that by 2020, more than 26 billion internet devices and connections universally interconnected will require nearly 3 times the data traffic generated when compared to the year 2015. The increase in data traffic, demands for enormous bandwidth capacity. The potential to deliver 10 Gbps of huge data to individual businesses and households will be of paramount importance and a challenging issue for the present day service providers. An intensive study is carried out for the Fiber-To-The-Home Passive Optical Network (FTTH PON) for their use in the optical communication, due to their high data rates and more bandwidth. The current evolution of Next Generation-Passive Optical Networks Stage 2 (NG-PON2) network is the primary key technology for the growing demands of higher bandwidth and transmission of the data to the subscribers present in the access network from the service providers. Time Wavelength Division Multiplexing PON (TWDM-PON) architecture is the viable essential solution for NG-PON2 which provides more bandwidth for bidirectional transmission. This article proposes a design for extended reach TWDM-PON based on reflective semiconductor optical amplifier (RSOA). The exclusive feature of the RSOA is the wavelength conversion, which replaces the transmitters in the subscriber end. The Quality of Service (QoS) performance is critically analyzed for different optical modulation formats in proposed extended reach TWDM-PON using RSOA. The TWDM-PON using RSOA is simulated and investigated for different photodetectors. The analysis is also carried for various distance and data rates. The results exhibited that APD receivers have better performance of minimum bit error rate obtained is 10-11 and minimum Q factor is 6.2 when compared with PiN receivers. The comparative analysis of different modulation formats shows that the Carrier Suppressed Return to Zero- Differential Phase Shift Keying (CSRZ-DPSK) gives the best performance for longer distance and large data rates and Return to Zero(RZ) gives the least performance.

High speed underwater visible light communication system based on LED employing maximum ratio combination with multi-PIN reception

In this paper, we proposed an underwater visible light communication system utilizing QAM-DMT and Multi-PIN reception to do the MRC receiving. The transmitter is a 600μm×600μm green-emitting silicon substrate LED which has a peak emission wavelength of 521 nm. We study the effect of quiescent working point of the LED, the zero-padding number, the ISFA tap number and the ratio of two receivers on the BER performance of our VLC system. We notice that the ratio of two receivers can remarkably affect the performance of our system. We also measured the BER performance versus the bandwidth of the signal in 32QAM, 64QAM and 128QAM modulation format and we find the highest data rate of our system can reach 2.175 Gb/s. As far as we know, it is the highest data rate in under pure water VLC system using commercial LED and a PIN receiver.

Simplified model for power penalty when using PIN and APD receivers

We present a characterization of power penalty using p-i-n (PIN) and avalanche photodiode (APD) receivers for different extinction ratios (ER) of the transmitted signal. A simple approach based on experimental fitting is presented to describe the power penalty. The model is in a good agreement with the experiment, predicting both PIN and APD results accurately, even considering that the characterized devices may vary considerably in their intrinsic parameters. The fitting parameter from the proposed model was extracted using a mean squared error (MSE) based fitting function. Theoretical curves were obtained by fitting the numerical results to the experimental data for MSE=10−3.

1.6 Gbit/s phosphorescent white LED based VLC transmission using a cascaded pre-equalization circuit and a differential outputs PIN receiver.

We proposed a cascaded amplitude equalizer used for high speed visible light communications (VLC) system. With the cascaded pre-equalization circuit, the -3dB bandwidth of VLC system can be extended from 17MHz to 366MHz using a commercially available phosphorescent white LED, a blue filter and a differential outputs PIN receiver. The data rate is 1.60Gbit/s exploiting 16QAM-OFDM with 400MHz modulation bandwidth over 1m free-space transmission under pre-forward error correction (pre-FEC) limit of 3.8 × 10(-3). To our knowledge, this is the highest data rate ever achieved by using a commercially available phosphorescent white LED in VLC system.

Integrated SOA-PIN Detector for High-Speed Short Reach Applications

Emergence of new applications like cloud computing, video on demand or deployment of high-speed cellular network lead to an increasing demand of high-speed short reach transmission for access network or datacenter. Due to the low sensitivity of PIN receiver and the lack of APD above 10 Gb/s, optical preamplification is a promising concept for high-speed receiver. We demonstrate an SOA-PIN/TIA receiver module which integrates an SOA-PIN photonic circuit and a TIA. This receiver has a large responsivity of 44 A/W, a polarization dependence below 2 dB, a low noise figure of 8.5 dB and a large 3-dB bandwidth of 35 GHz. Our new developed receiver achieved in NRZ a record sensitivity of -23 and -21 dBm at 25 and 40 Gb/s, respectively.

Practical 12.5-Gb/s, 12.5-GHz spaced ultra-dense WDM PON.

We report a practical 12.5-Gb/s, 12.5-GHz-spaced ultra-dense wavelength-division-multiplexed passive optical network (UD-WDM PON). For the cost-effectiveness, we implement the downstream links by using electro-absorption modulated lasers (EMLs) in the 4-level pulse amplitude modulation (4PAM) format and PIN receivers, and the upstream links by using reflective semiconductor optical amplifiers (RSOAs) modulated in the quadrature phase-shift-keying (QPSK) format and low-cost self-homodyne receivers. To further enhance its cost-effectiveness, we also utilize an optical frequency comb generator, instead of a large number of wavelength-selected lasers, to provide the seed light for these colorless RSOAs. We optimize the operating conditions of the EMLs and RSOAs to maximize the power margins in the presence of the crosstalk arising from closely spaced neighboring channels and the inter-symbol interference (ISI) caused by the narrow passband of the cascaded arrayed-waveguide gratings (AWGs) as well as the limited modulation bandwidths of RSOAs. The experimental results show that we can secure the power margins of >2.5 dB for both upstream and downstream links of the proposed UD-WDM PON.

Performance Comparison of PIN and APD based FSO Satellite Systems for various Pulse Modulation Schemes in Atmospheric Turbulence

In this paper, the performance of various Pulse Position Modulation (PPM) schemes has been analysed for PIN and APD receivers in the presence of atmospheric turbulence. It is observed that the performance of the APD receiver is always better than that of the PIN receiver as expected. Among the various modulation schemes, the performance of Differential Amplitude PPM (DAPPM) scheme with more number of amplitude levels is better than that of the other schemes for the same single level peak amplitude. Further, the optimum gain of APD receiver does not change substantially for different modulation schemes and turbulent conditions.

광통신시스템의 PIN 수신기 수신감도 해석

광통신 시스템에서 신호와 부가적인 잡음의 통계적인 특성에 대해 다양한 방법으로 평가하는 것은 시스템의 성능 최적화를 위해 필수적인데, 본 연구에서는 수신기의 성능 평가 방법으로 다양한 에러 확률을 대역폭과 비트수의 함수(m)로 표현하여 수신기의 성능을 평가를 통하여 광통신시스템에서 사용되고 있는 PIN 수신기의 수신감도를 해석하였고 시뮬레이션을 통해 이를 확인하였다. 그 결과 m=20인 경우, PIN 수신기의 수신 감도는 주어진 에러 확률을 유지하기 위해 대략 <TEX>$9.2{\times}10^4$</TEX> 광자/비트 정도가 필요함을 확인 할 수 있었다. It is essential to various evaluate about statistic character of the signal and additional noise for optimization of the optical communication system. We expressed various error probability with the m which was bandwidth and a bit numerical function and carried out performance evaluation of a PIN receiver. This research analyzed the receiving sensitivity of the PIN receiver and verified reception sensitivity through computer simulation in the optical communication system. As a result, the receiving sensitivity for PIN receiver are <TEX>$9.2{\times}10^4$</TEX> photon/bit for given error probability.

An approach to enhance the receiver sensitivity with SOA for optical communication systems

In this paper, we investigate an SOA (semiconductor optical amplifier) preamplifier structure by optimizing the carrier lifetime in order to reduce the amplified spontaneous emission (ASE) noise and crosstalk, with adequate gain increase. This proposed SOA optical preamplifier has no need of optical alignment and antireflection coating. This structure of SOA eliminates the need of optical filter, and exhibits large tolerance to the input light wavelength. The receiver sensitivity is investigated for single and multi channel transmission links. The received power of − 50.34 dBm is observed at bit error rate (BER) 10 − 12 for 10 Gb/s with PIN receiver. Further, the impact of gain, amplified spontaneous emission power and gain variation for different carrier lifetime with input power for OOK system is illustrated. The proposed SOA has constant gain of 30.06 dB up to gain saturation for carrier lifetime 0.18 ns. It is predicted that low value of carrier lifetime suffers less from ASE noise.

Spectrum-Sliced Wavelength Division Multiplexed Systems with Optical Preamplifiers

The effect of dispersion on a spectrum-sliced wavelength division multiplexed system with an optical preamplifier receiver is investigated using a theoretical model based on the statistics to improve understanding of spectrum slicing in a realistic situation, where dispersion significantly impacts the signal in transmission. The results show that the optically preamplified receiver delivers increased transmission capacity and a substantially improved power budget compared to a pin receiver. The results are obtained using the saddlepoint approximation and compared to the customary Gaussian approximation, which is found to be reasonably accurate in predicting the optimum bandwidth but conservative in sensitivity predictions.

Free-space optical communication employing subcarrier modulation and spatial diversity in atmospheric turbulence channel

An expression for the bit error rate of a multiple subcarrier intensity-modulated atmospheric optical communication system employing spatial diversity is derived. Spatial diversity is used to mitigate scintillation caused by atmospheric turbulence, which is assumed to obey log-normal distribution. Optimal but complex maximum ratio, equal gain combining (EGC) and relatively simple selection combining spatial diversity techniques in a clear atmosphere are considered. Each subcarrier is modulated using binary phase shift keying. Laser irradiance is subsequently modulated by a subcarrier signal, and a direct detection PIN receiver is employed (i.e. intensity modulation/direction detection). At a subcarrier level, coherent demodulation is used to extract the transmitted data/information. The performance of on-off-keying is also presented and compared with the subcarrier intensity modulation under the same atmospheric conditions.

Demonstration of 2.488 Gbit/s transmission on the UK—Channel Islands No 7 submarine cable system

The recently-installed UK--Channel Islands No 7 cable system is a 132 km unrepeatered, twelve optical fibre, 140 Mbit/s system. In February the cable was used for a series of tests to demonstrate new transmission and receiver equipment developed at British Telecom Research Laboratories (BTRL). The paper describes first the use of erbium fibre power amplifiers to achieve two-way transmission over the system at 2.488 Gbit/s, and then the testing of a novel semi-ruggedised laser PIN receiver.