Performance analysis of Modified 16-Channel WDM-RoF network for Efficient Long-Haul 5G Communication

HaldiaInstit u Int.J.HIT.T R     *Correspond i   ORIGINA Perfo r for Ef f Suman S Guru Jamb h Email Id: pr ABSTRA C This pape r Radio-ov e integrates FBGs pro v nonlinear d at a carri e achieving the prop o configurat high-capa c KEY WO R Conjugati o 1. INT R The everg users, co m rates, has frequency the milli m high-frequ e requireme n systems, p a ultra-high connectivi t Optical fi b effective t r (RoF) syst e low atten u cost effic i interferenc an efficie n (RF) sign a signal fid u teofTechnology R ANSC:ECCN. V i ng Address: p riya n L CONTRIB U r mance a f icient L o S ingh 1 , Priy a h eshwar Univer s r iyanka.dalal17 @ C T r presents the er -Fibre (WD M Fiber Bragg G v ide precise w d istortions, i m e r frequency o reliable trans m o sed 16-chan n ions, offerin g c ity long-haul R DS:WDMR o n (OPC), Lon g R ODUCTI O g rowing numb e m bined with t h led to the m bands to hig h m etre-wave ( m e ncy bands a r n ts of nex t - a rticularly 5G capacity, l o t y [1-4]. b er has esta b r ansmission m e ms due to its u ation, lightwe i i ency, and i m e [5-6]. Thes e n t medium for a ls over long elity [7-9]. C Publishing V ol.12:Issue1 A Availab l n ka.dalal17@gm a U TION a nalysis o o ng-Ha u a nka Dalal 1 , P s ity of Science a n @ gmail.com design and p e M -RoF) syste m G ratings (FB G w avelength filt m proving spe c o f 50 GHz wi t m ission over 3 n el WDM-R o g enhanced s i communicati R oF, Wavelen g g -Haul Comm u O N e r of wireless c h e demand f o m igration fro m h er frequency r mm -wave) sp e r e critical for - generation c and beyond, w o w latency, b lished itself m edium for R a unique prope r i ght nature, h i m munity to e e features ma k transporting r a distances whi l C ompared w i  A (2025)Page 4 l eOnlineat w AllRi a il.com o f Modi f u l 5G Co m P ravesh Ku m n d Technology, e rformance e v m for long-h a G s) and an Op t ering and dis p c tral efficienc y t h a data rate 3 40 km of sta n o F model e x i gnal integrit y on. g th Division M u nication, 5g N c ommunicatio n o r higher dat a m conventiona l r anges such a s e ctrum. Thes e addressing th e c ommunicatio n w hich deman d and reliabl e as the mos t a dio-over-Fibe r r ties, includin g i gh bandwidth lectromagneti c k e optical fibe r a dio frequenc y l e maintainin g i th traditiona l  4 9‐59  w ww.hithaldi a ghtsReserve f ied 16C m munic a m ari 1 and S a Dept. of E.E.E. , v aluation of a a ul 5G comm u t ical Phase C o p ersion mana g y and transmi s of 10 Gbps p n dard singlem x hibits supe r y , reduced di s M ultiplexing, F N etworks. n a l s e e n d e t r g , c r y g l wire l leve r supp high e To amp l Am p sign a acros s Radi addi t Mod u mod u miti g effe c selfp mod u ther e man a Co m Inter n ISSN: a .in/locate/E C d P C hannel W a tion a njeev Kum a , Hisar, India 16-channel W u nication net w o njugator (OP g ement, while s sion reach. T p er channel a m ode fiber. S i r ior perform a s persion effe c iber Bragg G r l ess transmis s r ages the va s ort a signific a e r transmissio n enable longh l ification is o f p lifiers (EDF A a l strength, co m s fiberspans[13 o-over-Fibre t ional comp o u lators (MZM u lation, while g ate the effec t c tively compe n p hase mo d u lation (XPM ) e by improvin g a gement is e q m pensating Fi b n ationalJournalo f 0973‐6875 C CN P age | 49 W DMR a r Dhull 1 W avelength D w orks. The p r C) to enhanc e the OPC effe c T he system is a nd a channel i mulation res u a nce compar e c ts, and impr o r ating (FBG), O s ion method s s t bandwidth a ntly larger n u n rates [10-12] . h aul RoF t r f ten required. E A s) play a k e m pensating fo r ]. In Wavelengt h (WDM-R o o nents such s) are employ e Optical Phase t s of nonline a n sates for im p d ulation (S P ) , and fou r -w a g system perf o q ually import a b er (DCF) co f HITTransaction o R oF net w D ivision Multi p r oposed archi t e signal qualit y c tively comp e designed to o spacing of 0 . u lts demonstr a e d to conve n o ved scalabil i O ptical Phase s , RoF tech n of optical fi b u mber of use r . r ansmission, o E rbiu m -Dope d e y role in b o r transmission h  Division Multi p o F) archite as Mach–Z e e d for efficient Conjugators ( a rities [14-15] p airments cau s P M), cros s a ve mixing ( F o rmance. Dis p a nt, with Dis p mmonly utili z o nECCN  w ork p lexed t ecture y . The e nsates o perate . 5 nm, a te that n tional i ty for n ology b re to r s and o ptical d Fiber o osting losses p lexed ctures, e hnder signal OPCs) . OPC s ed by s -phase F WM), p ersion p ersion z ed to Suman Singh et. al../ Int.J.HIT.TRANSC:ECCN. Vol.12: Issue 1A(2025)  ISSN:0973‐6875  Page|50 counteract chromatic dispersion in WDM transmission [16-18]. Despite these advancements, optical fiber communication still suffers from impairments such as attenuation, dispersion, and nonlinear effects, which degrade overall system performance [5][6]. To address these limitations, Fiber Bragg Gratings (FBGs) have been widely deployed in multi-channel WDM systems to suppress unwanted reflections, filter specific wavelengths, and reduce dispersioninduced distortions. By providing accurate wavelength selectivity and dispersion control, FBGs significantly enhance system efficiency and stability [19-20]. Consequently, WDM-RoF has emerged as a promising solution for robust, high-capacity, and scalable communication networks [21]. Building upon prior research on 4-channel and 8-channel WDM-RoF systems, this work advances the field by developing and analyzing a 16-channel WDM-RoF architecture [22]. The proposed system integrates OPC and FBG components to improve signal integrity, suppress nonlinear impairments, and extend transmission distance, thereby addressing the increasing demands of long-haul 5G communication networks [23-24]. The operation of FBGs is based on the Bragg reflection principle, where the central reflected wavelength is determined by the following relation: 𝜆  2𝜂𝑒𝑓 𝛬(1) Where, ηef is the core effective index, and Λ is the grating period. The scalability and performance of the system are validated through simulation, demonstrating its potential as a cost-effective and reliable approach for next-generation communication infrastructures. 2. SYSTEM DESIGN The proposed 16-channel WDM-RoF system is modelled and analysed using OptiSystem simulation software. The setup employs multiple continuous-wave (CW) laser sources, each operating around the standard reference wavelength of 1550 nm, with a uniform channel spacing of 0.5 nm, as illustrated in Fig. 1. This configuration ensures efficient wavelength allocation and supports high-capacity transmission. The overall architecture of the system is divided into two primary subsystems: the transmitter and the receiver, as depicted in Fig. 2, Fig. 3 and Fig. 4, respectively. At the transmitter side, each laser source is externally modulated using a dual-drive Mach–Zehnder Modulator (MZM). This modulation scheme enables efficient conversion of electrical data signals into the optical domain, ensuring broad bandwidth and stable transmission. Table 1: Wavelength utilization in the proposed system corresponding to each channel. Channel No. Wavelength (nm) Channel No. Wavelength (nm) Ch 1 1550 Ch 9 1554 Ch 2 1550.5 Ch 10 1554.5 Ch 3 1551 Ch 11 1555 Ch 4 1551.5 Ch 12 1555.5 Ch 5 1552 Ch 13 1556 Ch 6 1552.5 Ch 14 1556.5 Ch 7 1553 Ch 15 1557  ISSN:0973 The mu l combined which is t optical fi b To mitig a chromati c an OPC transmiss i At the r e optical-to - selected f characteri advantag e long-dist a filter is frequenc y signal rec o Finally, W analysers ‐6875 Ch 8 l tiplexed o p to form a 1 t ransmitted o v b er link. a te transmis s c dispersion a is strategi i on path. T F e ceiver side, - electrical c o f or its high stics, wh i e ous for det e a nce transmis s further emp y noise com p o very. W DM analy s are integr a  155 p tical signa l 1 6-channel W v er a 340 k m s ion impair m a nd nonline a cally place d T he OPC F igure1: Bas an APD i s o nversion. T sensitivity a n i ch are e cting weak s ion. A lowp l oyed to s u p onents, ens u s ers and opt i a ted into t h Suman Si n 3.5 l s are the n W DM stream , m single-mod e m ents such a s a r distortions , d along th e generates a ic Block di a s utilised fo r T he APD i s n d low-nois e particularl y signals afte r p ass electrica l u ppress high - u ring accurat e i cal spectru m h e design t o n gh et. al../ Int. J n , e s , e a conj u effe c and FB G filte r and imp r a gram of the r s e y r l - e m o eval u incl u qual the The s com b ens u rate s opti c J .HIT.TRANS C Ch 16 u gated repl i c tively canc e improving G s are emp l r s to manag e enhance w r oving signal WDMRo F u ate key sys t u de OSNR a n ity indicator s proposed 1 s trategic use b ined with e u res improve d s , and robu s c al communi c C :ECCN. Vol. 1 1557.5 i ca of the e lling phase - system line a l oyed as w a e dispersion, w avelength integrity acr o F network t em perform a n d SNR and s that reflec t 6-channel W of OPC a n e ffective de t d signal qua l s t perfo r man c c ation links. 1 2: Issue 1A(2 0 Pag e distorted s - related dist o a rity. In ad d a velength-sel suppress cro s stability, t h o ss all chann e a nce metrics. other trans m t the efficie n W DM-RoF m n d FBG ele m t ection tech n l ity, enhance d c e over lon g 0 25) e |51 s ignal, o rtions d ition, ective s stalk, h ereby e ls. These m ission n cy of m odel. m ents, n iques, d data g -haul  ISSN:0973 Figure 3: The figur e the desig n side, a P generator using a N modulate d (MZM). A 1550 nm ‐6875 Figure 2:S c SenderFig u e illustrates t h n ed RoF sy seudo-Rand o produces in p N on-Return-t o d through a M A continuou s serves as t h  c hematic la y u re 4: Recipi h e overall co n stem. On t h o m Bit Sequ e p ut data, whi c o -Zero (NRZ ) M ach–Zehnd s -wave laser h e optical ca r Suman Si n y out of the p r ent n figuration o f h e transmitte r e nce (PRBS ) c h is encode d ) encoder an d er Modulato r operating a t r rier, while a n gh et. al../ Int. J r oposed sin g  f r ) d d r t a dual exte r sign a tran s Fig u WD M [25] . J .HIT.TRANS C g le-channel W -drive LiN b r nal modula t a l generatio n s mitted ove r a u re 2 illustrat e M -RoF syste . C :ECCN. Vol. 1 W DM-RoF b O₃ MZM t ion, enablin g n . The mod u a single-mod e e s the simul a m incorpora t 1 2: Issue 1A(2 0 Pag e system.  is employe d g efficient o u lated signa l e fiber link. a ted single-c h t ing FBG an d 0 25) e |52 d for o ptical l s are h annel d OPC  ISSN:0973 To mitig a long-haul span, in c and nonl i end, the Gaussian b y an A P reduced enhances improved Figure 5 s RoF net w represent e architectu respectiv e Figure 2 i WDM-R o [25]. Th proposed integrates including ‐6875 Figure 5 a te impairm transmissio n onjunction w i nearity man a optical sign a low-pass fil t P D, ensuring noise. Th e transmissio n signal qualit y s hows the pr o w ork, with t r e d as bloc k res are deta i e ly. i llustrates th e o F system in c e transmitt e 16-chann e several a PRBS gen e  5 : Schemati c ents accum u n , an OPC i s w ith an FBG f a gement. At a ls are pass e t er before b e improved s e e overall n performan c y over exten d o posed 16-c h r ansmit t ers a k s, while t h i led in Figu r e simulated s i c orporating F B e r configura t e l WDMR functional e rator, NRZ p Suman Si n c layout of th e u lated durin g s placed mid - f or dispersio n the receive r e d through a e ing de t ecte d e nsitivity an d configuratio n c e, providin g d ed distances. h annel WDM - a nd receiver s h eir interna l r es 3 and 4 , i ngle-channe l B G and OP C t ion of th e R oF syste m components , p ulse encoder , n gh et. al../ Int. J e proposed 1 6 g - n r a d d n g - s l , l C e m , , cont osci l as o enh a mul t and opti c 16 u To a OP C opti c also conj u of t h opti c 𝐸 󰇛 the equi v the i 𝐸  J .HIT.TRANS C 6 -channel W D inuous-wave l lator, DC bi a o utlined in F a nces the tra n t iple optical c subsequentl y c al fiber usi n u nique carrier a ddress nonli n C is employe d c al amplifier referred to a s u gated optic a h e original s c al field as: 󰇛 𝑡󰇜  𝐴󰇛𝑡󰇜𝑒 ∅ phase-conju g v alent to ta k nput, yieldin g  󰇛𝑡󰇜  ηA󰇛t󰇜 e C :ECCN. Vol. 1 D M-RoF syst e laser s o a s generator, F ig. 3. The n smission ca p c arriers at d i y combining n g a multiple x frequencies a n ear distortio n d in conjuncti s and dual s wavefront r e a l wave by i n s ignal. Rep r e ∅  g ated signal k ing the co m g : e ∅∅ 1 2: Issue 1A(2 0 Pag e e m. o urce, sin u and a dual M WDM trans p acity by pro d i stinct wavel e them into a x er. In this d a re generated n s in the fibe r on with distr i fiber spans. e versal, prod u n verting the e senting the ( 2 is mathema t m plex conjug a (3 ) 0 25) e |53 u soidal M ZM, mitter d ucing e ngths single d esign, . r link, i buted OPC, u ces a phase input 2 ) t ically a te of ) Suman Singh et. al../ Int.J.HIT.TRANSC:ECCN. Vol.12: Issue 1A(2025)  ISSN:0973‐6875  Page|54 where η represents the device efficiency. The combination of OPC with reversed propagation effectively compensates for nonlinear phase distortions and waveform impairments encountered in optical transmission. FBG operates on the principle of Bragg reflection, which occurs due to a periodic refractive index modulation within the optical fiber. This periodic structure is inscribed along a specific length of the fiber, unlike the uniform refractive index of a standard fiber core that typically allows light to propagate without reflection. However, when a periodic refractive index modulation is introduced, it forms a “grating” structure within the fiber. The refractive index modulation is typically achieved by using an ultraviolet (UV) laser to expose the fiber core to intense UV light through a phase mask or interferometric technique. The UV light causes a photosensitive change in the fibers refractive index, resulting in a periodic fluctuation in the refractive index profile. When light propagates through the fiber and encounters the FBG, a portion of the incident beam is returned due to the periodic refractive index modulation. This reflection occurs at a certain wavelength resolved by the period of the grating. This wavelength is called the Bragg wavelength (𝜆𝐵𝑟𝑎𝑔𝑔) and is given by the Bragg condition [1][25]. 𝜆𝐵𝑟𝑎𝑔𝑔  2∗𝛬∗ 𝑛𝑒𝑓𝑓 (4) where, Λ = the period of the grating 𝑛 = the effective refractive index The Bragg condition guarantees that reflected light waves undergo constructive interference, thereby producing a strong reflection precisely at the Bragg wavelength. Conversely, wavelengths outside this range propagate through the grating with negligible reflection. By adjusting the grating period and fabrication parameters, an FBG can be tailored to operate either as a narrowband reflector or as a broadband filter. Moreover, tilted grating structures can be employed to control the reflection angle, offering additional flexibility in design. On the receiver side, the system integrates a wavelength demultiplexer, a Gaussian optical filter, and an APD shown in Fig. 4. The demultiplexer separates the multiplexed optical carriers into their individual channels, after which the Gaussian filter suppresses unwanted noise and out-of-band components. The filtered signal is then converted into an electrical domain by the APD. To restore the original data quality, a signal regenerator is incorporated, while a BER) tester evaluates system performance in terms of OSNR and SNR under varying distances. Table 2 outlines the simulation parameters used in this study along with their assigned values. Table 2. Simulation factors. Parameter Value Modulation Scheme LiNb-MZM Suman Singh et. al../ Int.J.HIT.TRANSC:ECCN. Vol.12: Issue 1A(2025)  ISSN:0973‐6875  Page|55 Bit rate 10 Gbps Radio signal frequency 50 GHz Reference wavelength 1550 nm Wavelength spacing 0.5 nm OSNR & SNR Measurement WDM Analyzer  3. RESULTS AND DISCUSSIONS The system is designed using OptiSystem, and its performance is evaluated in terms of OSNR and SNR with respect to transmission distance, bit rate, and carrier frequency. The simulated performance of the proposed 16channel WDM-RoF system is analyzed in terms of key quality metrics, namely OSNR and SNR. Particular emphasis is placed on evaluating the impact of increasing transmission distance on system efficiency. The assessment is carried out for distances ranging from 50 km to 340 km, thereby enabling an in-depth understanding of the system’s transmission capability over longhaul fiber links. Each of the 16 channels operates within the wavelength range of 1550 nm to 1557.5 nm, with a uniform channel spacing of 0.5 nm. The system is simulated at a data rate of 10 Gbps per channel and a 50 GHz RF carrier frequency, providing a robust basis for performance evaluation. The simulation results are summarised in Tables 3 and 4, corresponding to OSNR and SNR variations across different channels and transmission distances. Table 3 presents the OSNR values (in dB) for the 16-channel system. The results demonstrate a gradual reduction in OSNR with increasing fiber length. For example, Ch 1 records an OSNR of 53.31 dB at 120 km, which decreases to 31.35 dB at 340 km, whereas Ch 15 shows 35.13 dB at 120 km, reducing to 17.08 dB at 340 km. The analysis confirms that the OSNR values across all channels remain above the minimum acceptable threshold of 16 dB within the range of 120 km to 340 km, as illustrated in Fig. 6. This indicates that the proposed system ensures reliable transmission performance over long-haul distances. However, the expected degradation in OSNR with distance is primarily attributed to fiber attenuation and chromatic dispersion. Table 3. Variation of OSNR (dB) for Ch 1 to 16 with transmission distance. Distance(km) Channel(Wavelength(nm)) Ch1 Ch3 Ch5 Ch7 Ch9 Ch11 Ch13 Ch15 120 53.31 51.24 49.24 47.76 44.17 42.76 39.45 35.13 Suman Singh et. al../ Int.J.HIT.TRANSC:ECCN. Vol.12: Issue 1A(2025)  ISSN:0973‐6875  Page|56 160 51.85 48.62 46.59 45.70 42.75 39.38 38.19 34.85 200 50.89 47.86 44.82 41.79 38.72 37.32 35.59 33.25 240 47.41 45.92 42.89 39.85 36.81 33.65 30.59 27.79 280 40.7937.73 34.98 33.97 31.71 29.41 28.40 25.19 320 36.65 33.20 30.65 29.31 27.89 23.81 19.75 18.61 Table4providestheSNRresultsforall16channelsacrossthesametransmissionrange.The trendisconsistentwiththeOSNRobservations,showingdecreasingSNRwithdistance. Table 4. Variation of SNR (dB) for Ch 1 to 16 with transmission distance. Distance(km)Channel(Wavelength(nm)) Ch1Ch3Ch5Ch7Ch9Ch11Ch13Ch15 12053.2351.7850.7247.6544.8 1 41.8940.1535.30 16052.3848.5446.7944.1142.8 4 40.1936.9835.62 20050.6949.7747.1044.9140.9 2 38.1635.8133.42 24047.7845.6743.1941.8639.7 6 37.6533.5531.29 28042.1740.8238.9835.8733.9 5 31.2228.7825.45 32038.2835.2332.4730.7528.6 8 25.8220.3218.38  For instance, Ch 1 exhibits an SNR of 53.23 dB at 120 km, reducing to 30.41 dB at 340 km, while Channel 15 decreases from 35.30 dB at 120 km to 16.13 dB at 340 km. Despite this decline, the system maintains SNR values well Suman Singh et. al../ Int.J.HIT.TRANSC:ECCN. Vol.12: Issue 1A(2025)  ISSN:0973‐6875  Page|57 above 18 dB across all channels for distances up to 340 km, as depicted in Fig. 5. This highlights the system’s capability to support high-quality signal transmission, although dispersion and attenuation effects remain significant limiting factors over extended distances. Figure 6: Distance vs OSNR Figure 7: Distance vs SNR Table 5. OSNR Comparison of the 16-Channel WDM-RoF Network: Proposed vs. Existing Work. Existing Work[1] Proposed 16-Channel WDM-RoF System Distance 90 km 110 km 120 km 160 km 200 km 240 km 280 km 320 km 340 km Ch 1 65.08 52.82 53.31 51.85 50.89 47.41 40.79 36.65 31.35 Ch 3 64.48 56.66 51.24 48.62 47.86 45.92 37.73 33.20 26.31 Ch 5 61.93 50.69 49.24 46.59 44.82 42.89 34.98 30.65 25.41 Ch 7 41.27 25.68 47.76 45.70 41.79 39.85 33.97 29.31 23.29 Ch 9 - - 44.17 42.75 38.72 36.81 31.71 27.89 20.66 Ch 11 - - 42.76 39.38 37.32 33.65 29.41 23.81 18.49 Ch 13 - - 39.45 38.19 35.59 30.59 28.40 19.75 17.65 Ch 15 - - 35.13 34.85 33.25 27.19 25.19 18.61 17.08