Implementasi bandpass filter m-derived pada pemancar radio FM

Pemancar siaran radio FM adalah salah satu sistem komunikasi nirkabel, bekerja rentang frekuensi 88-108 MHz membutuhkan sebuah filter bandpass untuk menghindari adanya interferensi dengan frekuensi yang berdekatan dengan pemancara radio. Jenis filter yang memiliki performansi cukup baik adalah filter dengan tingkat kecuraman yang cukup tinggi. Namun, untuk mendapatkan tingkat faktor kecuraman yang tinggi dengan menambah beberapa elemen. Maka, pada penelitian ini menambahkan rangkaian m-derived utnuk memberikan respon filter yang lebih curam tanpa menambahkan nilai elemen yang banyak. Tujuan penelitian ini mengetahui perbandingan daya pemancar tanpa filter, dengan bandpass filter, dan menggunakan bandpass filter m-derived. Hasil pengujian daya pancar tanpa filter sebesar 2 Watt, dengan menggunakan bandpass filter daya pancar sebesar 1,05 Watt, sedangkan dengan menggunakan bandpass filter m-derived daya pancar sebesar 1,4 Watt. Kesimpulannya pelemahan (insertion loss) pada Bandpass Filter sebesar 2,53 dB sedangkan pelemahan (insertion loss) pada BPF m-derived section sebesar 1,54 dB dengan menambahkan BPF m-derived section memperbaiki daya keluaran pemancar lebih besar 0,35 W atau 1,01 dB dibandingkan dengan pemancar yang menggunakan BPF tanpa m-derived. FM radio broadcast transmitter is a wireless communication system, with frequency range of 88-108 MHz requires a bandpass filter to avoid interference with frequencies adjacent to radio transmitters. The type of filter that has a fairly good performance is a filter with a fairly high level of steepness. However, to get a high level of steepness factor by adding some elements. So, in this study, we added an m-derived circuit to provide a steeper filter response without adding a lot of element values. The purpose of this study is to compare the transmitter power without a filter, with a bandpass filter, and using an m-derived bandpass filter. The result of testing the unfiltered transmit power is 2 Watt, using a bandpass filter the transmit power is 1.05 Watt, while using the m-derived bandpass filter the transmit power is 1.4 Watt. In conclusion, the insertion loss in the Bandpass Filter is 2.53 dB, while the insertion loss in the BPF m-derived section is 1.54 dB by adding the BPF m-derived section to improve the transmitter output power by 0.35 W or 1 .01 dB compared to transmitters using BPF without m-derived.

BER Illusion Methodology: A Novel, Open Sourced and Scalable Approach to Troubleshooting High Radix Photonics Interconnects in a Modern Hyperscale Datacenter

Facebook Datacenter consists of a large number of servers that run diverse Facebook services aggregated to serve any given user request. To allow this aggregation, servers have to interact with each other via different traffic flows which are managed by networking fabric. The underlying connection powering this fabric consists of a large number of pluggable optical interconnects and On Board Optical (OBO) modules carrying production data. This connectivity at scale requires fast and reliable detection of the link failures to ensure resolution. In the first generation of the deployments, detection of the link failure was sequential and a slow process. The troubleshoot process was equally tedious as the available tools required characterizing one optical transceiver at a time. Further, the failure analysis also presented a majority of resolution with no failed optics as a root cause resulting in high No Trouble Found (NTF) rate. In this paper we introduce a novel link failure detection and resolution method that improves on the previous method across three dimensions: faster resolution, reliable troubleshooting and scalable implementation. We introduce BER Illusion Methodology (BIM) that is a highly scalable and resource efficient solution that significantly reduces the time taken to troubleshoot pluggable optical interconnects. This is also scalable to next-gen OBO modules at Facebook datacenters aiming to lower the NTF rate and optimally utilizing the available resources. BIM, which is based on Open Compute Platform (OCP) network switches, can be used to troubleshoot 128 QSFP28, 64 QSFP56 or 32 OBO modules simultaneously in under 30 minutes. The tool is easy to implement and capable of also reporting diagnostics on the transceiver such as Transmitter Power, Transmitter Bias Current, Receiver Power, Case Temperature, Bit Error Rate result per channel, Vendor information and Manufacturing part number. This additional test data report along with true failure indication helps optic suppliers gain confidence and build customer credibility. The open-source nature and the universal applicability of this tool offers possibility for other users to adopt and further customize it for their networking needs.

Performance Tradeoff Analysis of Hybrid Signaling SWIPT Systems with Nonlinear Power Amplifiers

Simultaneous wireless information and power transfer (SWIPT) is a promising technology to achieve wide-area energy transfer by sharing the same radio frequency (RF) signal and infrastructure of legacy wireless communication systems. To enlarge the effective range of energy transfer in practice, it is desirable to have a hybrid signaling SWIPT scheme, which combines a high-power multitone energy signal with a low-power broadband information signal. This paper presents a systematic study on the performance of hybrid signaling SWIPT systems with memoryless nonlinear transmitter power amplifiers (PAs). Using PA efficiency and signal-to-noise-and-distortion ratio (SNDR) as the metrics to measure the efficiency of energy transfer and information transmission, respectively, we derive the tradeoff between these two metrics for two PA classes, two nonlinear PA models, and two SNDR definitions. Our results reveal insights into the fundamental performance tradeoff inherent in SWIPT systems using hybrid signaling schemes.

Acoustic telemetry detection probability and location accuracy in a freshwater wetland embayment

Background In recent years, large-scale acoustic telemetry observation networks have become established globally to gain a better understanding of the ecology, movements and population dynamics of fish stocks. When studying a species that uses different habitats throughout its life history difficulty may arise where acoustically suboptimal habitats are used, such as shallow, vegetated areas. To test the feasibility of active tracking in these acoustically suboptimal habitats, we quantified detection probability and location error as a function of several environmental variables with two transmitter types in a shallow freshwater embayment. Results When placed in nearshore areas (< 1 m deep), the higher-powered transmitter (158 dB) had significantly greater detection probability than the lower-powered transmitter (152 dB). For both transmitter types, detection probability declined at 200 m; however, at the 100 m distance the higher-powered transmitter had greater than 50% detection probability per ping cycle (50.4%) while the lower-powered transmitter was substantially less (29.4%). Additionally, detection probability increased when the transmitter was deployed within sparse, senescent Phragmites spp. vegetation (14%). Estimated positional accuracy of transmitters deployed at known locations (location error) was variable (error range: 13–259 m), and was generally higher for the more powerful transmitter. Location error was minimized when the lower-powered transmitter was located near softened shoreline areas compared to near man-made armored shorelines (i.e., rip-rap). Conclusion While benefits exist for maximizing transmitter power (e.g., increased detection range in open-water environments), use of a lower-powered transmitter may be advantageous for active tracking specific locations of fish inhabiting shallow water environments, such as in estuarine tidal marshes and shallow wetlands. Thus, when planning acoustic telemetry studies, researchers should conduct site-specific preliminary detection probability/location error experiments to better understand the utility of acoustic telemetry to investigate fish movements in acoustically suboptimal conditions.

Cellular Communication Propagation at Drone around Building Environment with Single Knife Edge at 10 GHz

The drone communication systems used a cellular network for controlling a drone from a long distance. That communication propagations between drone and base station were analyzed. The drone moved at the track around building environment. That environment used variations in building height. The communication propagation around building environment caused diffraction mechanism. Single knife edge method is used for that diffraction mechanism. The frequency of communication used 10 GHz. That frequency was influenced by atmospheric attenuation. This research was using some variations such as height of drone track location, transmitter power, and AMC (Adaptive Modulation Coding). MCS (Modulation Coding Scheme) was used AMC such as QPSK, 16 QAM, and 64 QAM. Some result was obtained at this research consist of LOS and NLOS distance, SNR, MCS probability, and percentage of drone coverage. NLOS propagation was caused by building height. The SNR value become increase when higher at drone position, such as drone was moving at 20 meters with height of flying drone 80 m and transmitter power 30 dBm obtained SNR 38.21 dBm. That SNR is affected AMC, so a higher SNR value increases AMC. The drone’s coverage 100%, with a height of flying drone 80 meters and transmitter power of 30 dBm. That condition showed more increasing coverage percentage than 64.8% for height of flying drone 20 meters and transmitter power 30 dBm. That result showed that more drone height increased of coverage percentage, probability modulation, and SNR value.

Wavelet Neural Networks and Equalization of Nonlinear Satellite Communication Channel

Wavelet neural networks are a class of single hidden layer neural networks consisting of wavelets as activation functions. Wavelet neural networks (WNN) are an alternative to the classical multilayer perceptron neural networks for arbitrary nonlinear function approximation and can provide compact network representation. In this chapter, a tutorial introduction to different types of WNNs and their architecture is given, along with its training algorithm. Subsequently, a novel application of WNN for equalization of nonlinear satellite communication channel is presented. Nonlinearity in a satellite communication channel is mainly caused due to use of transmitter power amplifiers near its saturation region to improve efficiency. Two models describing amplitude and phase distortion caused in a power amplifier are explained. Performance of the proposed equalizer is evaluated and compared to an existing equalizer in literature.

Doppler Shift Effect at The Communication Systems with 10 GHz around Building

This research described the Doppler shift effect for the communication systems. The mobile station moves with various velocities around the building’s environment. Doppler’s shift influences the communication systems. The frequency communication was used 10 GHz and its influenced by atmospheric attenuation. This research consisted of propagation with LOS and NLOS conditions, mobile station velocity variation, height buildings variation, and transmitter power variation. This research described frequency maximum at Doppler shift, coherence time, and signal to noise ratio. More increase Doppler shift of coherence time caused signal noise ratio to decrease.

DETERMINANT FACTOR OF LISTENER LOYALTY TO POP FM JAKARTA

This study aims to analyze the influence of radio programs, broadcasters and transmitter power on listening to Pop FM radio Jakarta and listeners loyalty. Primary data were obtained from questionnaires and secondary data were obtained from field research such as interviews with companies. The population of this study were all listeners of Pop FM Jakarta radio in Jabodetabek in May-June with a total sample of 210 people. The analytical method used is the LISREL version 8.80 Structural Equation Modeling (SEM). The results showed that radio programs, broadcasters and transmitter power had a significant positive effect on interest in listening to radio. Meanwhile, radio programs, broadcasters and transmitter power also have a significant positive effect on radio listeners' loyalty. The R Square value is 0.75 that in this study the broadcast program variables, announcers and transmitter power contributed 75%, the rest was influenced by other variables by 25%

Comparative analysis of SISO and wavelength diversity-based FSO systems at different transmitter power levels

Free space optical (FSO) communication refers to a line of sight technology, which comprises optical source and detector to create a link without the use of physical connections. Similar to other wireless communication links, these are severely affected by losses that emerged due to atmospheric turbulence and lead to deteriorated intensity of the optical signal at the receiver. This impairment can be compensated easily by enhancing the transmitter power. However, increasing the transmitter power has some limitations as per radiation regulations. The requirement of high transmit power can be reduced by employing diversity methods. This paper presents, a wavelength-based diversity method with equal gain combining receiver, an effective technique to provide matching performance to single input single output at a comparatively low transmit power.

FSO Communication: Benefits, Challenges and Its Analysis in DWDM Communication System

Free-space optical (FSO) communication is one of the choice of researchers for most of the bandwidth hungry applications in evolving networks where the deployment of optical fiber is not directly possible as a transmission medium. In this research article, benefits, challenges, applications and role of FSO is discussed in detail for evolving networks. Further, performance of FSO communication system is tested using four channels of dense wavelength division multiplexing (DWDM). Various simulations are performed on FSO including different weather conditions, that directly affect the link performance. Many important parameters such as distance, data rate, bit error rate, amplifier gain, transmitter power, and attenuation under different weather conditions are tested in this research work. The operation of FSO communication system is carried out in the range 760-850 nm where equal channel spacing is considered for the working of DWDM communication system. Moreover, a fair comparison of proposed system is also presented for its operation in two more bands i.e. C and L-band, to show which one offers better performance. Simulation are performed in licensed version of Optisystem 14.0 and MATLAB. For the analysis of proposed system, results are presented in the form of BER and Q-factor plots.