Time filter

Source Type

Kuala Selangor, Malaysia

Salleh M.S.,TM RandD Sdn Bhd | Supaat A.S.M.,University of Technology Malaysia | Idrus S.M.,University of Technology Malaysia | Yaakob S.,TM RandD Sdn Bhd | Yusof Z.M.,TM RandD Sdn Bhd
Optik | Year: 2014

In this letter, we propose a new architecture of Time Wavelength Division Multiplexing Passive Optical Network (TWDM PON) system to support dynamic multi wavelength allocation (DMWA) in both upstream and downstream directions using an integrated semiconductor optical amplifier (SOA) and arrayed waveguide grating (AWG) with multi wavelength select continuous wave (CW) pump probe signal module. The significance of this architecture is the flexible routing function with the capability of multicasting and broadcasting between multiple optical line terminal (OLT) PON port with multiple optical distribution network (ODN) link using a new wavelength tuning free (WTF) OLT transmitter module to eliminate wavelength tuning delay in downstream signal utilizing multicasting Cross Gain Modulation (XGM) wavelength conversion. The experimental results show that 4λ × 10-Gb/s TWDM PON system can be used to connect 4096 users with the conventional fixed wavelength OLT transceivers with 36 dB link loss. © 2014 Elsevier GmbH. All rights reserved. Source

Salleh M.S.,TM RandD Sdn Bhd | Salleh M.S.,University of Technology Malaysia | Supa'At A.S.M.,University of Technology Malaysia | Idrus S.M.,University of Technology Malaysia | And 3 more authors.
Journal of Computer Networks and Communications | Year: 2014

We propose a new architecture of dynamic time-wavelength division multiplexing-passive optical network (TWDM-PON) system that employs integrated all-optical packet routing (AOPR) module using 4 × 10 Gbps downstream signal to support 20 km fiber transmission. This module has been designed to support high speed L2 aggregation and routing in the physical layer PON system by using multicasting cross-gain modulation (XGM) to route packet from any PON port to multiple PON links. Meanwhile, the fixed wavelength optical line terminal (OLT) transmitter with wavelength tuning free features has been designed to integrate with the semiconductor optical amplifier (SOA) and passive arrayed waveguide grating (AWG). By implementing hybrid multicasting and multiplexing, the system has been able to support a PON system with full flexibility function for managing highly efficient dynamic bandwidth allocation to support the 4 × 10 Gb/s TWDM-PON system used to connect 4 different PON links using fixed wavelength OLT transceivers with maximum 38 dB link loss. © 2014 M. S. Salleh et al. Source

Mohd Marzuki A.S.,TM RandD Sdn Bhd | Selamat S.,TM RandD Sdn Bhd | Naemat A.,TM RandD Sdn Bhd | Khalill K.,TM RandD Sdn Bhd | And 2 more authors.
IEEE Symposium on Wireless Technology and Applications, ISWTA | Year: 2013

This paper presents a planar bandpass filter design and its realization using 127μm RT/Duroid 5880 for 40GHz wireless communications applications. The filter has been designed at the center frequency of 41GHz with 2GHz passband using classical hairpin structure. The hairpin filter layout formulation is presented. Agilent's Advanced Design System Momentum is then used to carry out the EM simulation. The finalized filter layout is fabricated using the standard single-layer Printed Circuit Board (PCB) process. The fabricated filter shows 3.5dB insertion loss in the desired frequency range and the return loss is better than 10dB. © 2013 IEEE. Source

Marzuki A.S.M.,TM RandD Sdn Bhd | Naemat A.,TM RandD Sdn Bhd | Selamat S.,TM RandD Sdn Bhd | Tee A.T.M.A.,TM RandD Sdn Bhd | And 2 more authors.
RFM 2013 - 2013 IEEE International RF and Microwave Conference, Proceedings | Year: 2013

This paper presents the implementation of classical hairpin filter using Printed Circuit Board (PCB) for gigabit wireless application in the millimeter-wave band. The filter has been designed for 2GHz bandwidth at 41GHz center frequency. The filter samples were fabricated using 127μm thick Rogers RT/Duroid 5880 with Ground-Signal-Ground (GSG) pads to facilitate probe measurement. The first cycle of fabrication revealed that the Dielectric Constant (Dk) for designing hairpin filter using RT5880 is lower than the specified process Dk. The second trial exposed that hairpin filters are very sensitive to process tolerance. The filters for the subsequent fabrication manipulated design Dk of 2.1 and tighter process tolerance. The filters then show improved passband shape and return loss. However, the fabricated filters provide larger passband with slightly shifted center frequency than the simulated result due to inaccurate setting in the simulation tool. Nevertheless, the fabricated filters are still valid to be used for the intended application. © 2013 IEEE. Source

Marzuki A.S.M.,TM RandD Sdn Bhd | Naemat A.,TM RandD Sdn Bhd | Selamat S.,TM RandD Sdn Bhd | Tee A.T.M.A.,TM RandD Sdn Bhd
2012 IEEE Asia-Pacific Conference on Applied Electromagnetics, APACE 2012 - Proceedings | Year: 2012

This paper presents the interference study between CDMA850 and WCDMA900 in Malaysia. Both Frequency Division Duplex (FDD) systems are adjacent to one another spectrally without definite guard band and their coexistence becomes an issue when they are on reverse duplex. The WCDMA900 sites have claimed interference from CDMA850 Base Station transmitter. An affected site in Klang Valley is chosen to present the real case of interference between the two systems. A scheduled field test involving the closing of CDMA850 carrier is performed to investigate the main cause of interference. It is established that receiver blocking and/or receive intermodulation contributes the most to the WCDMA900 uplink interference for the selected site. A deterministic approach is then used to further analyze the minimum physical separation required to avoid receiver blocking and receive intermodulation. Additional filtering at the victim side is then recommended among the mitigation techniques to minimize the interference. © 2012 IEEE. Source

Discover hidden collaborations