Osama W. Ata

Palestine Polytechnic University · Department of Electrical Engineering

The Microwave Optical Duplex Antenna Link/MODAL project explores the application of advanced optical fibre technology to support the generation/delivery at a remote antenna site of millimetre wave signals, for future mobile radio and related applications. Patch array antennas are designed as the most suitable ones for integration on the same circui...

Linearisation of a radio basestation amplifier using a third order and a fifth order predistortion scheme is studied. Adaptive predistortion using a third order predistorter improved the amplifiers intermodulation distortion by between 6.5 dB and 30 dB as measured by a two tone test. The variation in improvement is due to changes in the input power...

The choice of the spatial frequency reuse and the channel plan in multi-cellular wireless systems plays an important role in effectively combating co-channel interference (CCI) and enhancing system capacity. In this paper, we compare the performance of four different interleaved channel and polarization assignment combinations of three spatial freq...

A new, circularly polarized small-size square microstrip antenna using a dual feed with 90 degree phase shift and central X-shaped slits is proposed. FR4-Epoxy substrate of thickness 1.6 mm and dielectric permittivity 4.4 was used in the simulated design on Ansoft-HFSS. The frequency of design was considered at 1 GHz, since the available antenna me...

The exploration of wireless alternatives to Broadband access has continued to be very important to service providers. The Line-of-Sight (LOS) Free Space Laser (FSL) and 60-GHz radios are two promising wireless alternatives since they fall in the FCC license-free spectrum and thereby mitigate the tremendous expense of spectrum acquisition. However,...

This article demonstrates a novel design of a split-bowtie slotted multi-resonant antenna. The design process was inspired from previous research of integrating a slot of a similar profile to the outer boundary of a rectangular patch antenna. The followed approach presents steps of proposed antenna evolution, which starts with a bowtie-shape slotte...

Multiband applications can be realized as a result of designing a double U-slot rectangular patch antenna. The equivalent circuit of a U-slot patch is presented and the return loss is theoretically derived, utilizing the [A] matrix formulation. CST Microwave Studio software was used to design the microstrip antenna with a transmission line feed and...

Ineffective deployment of carriers and sector load balancing are causing a significant poor carrier utilization in vendor markets. While identified performance carriers need to be retained, underutilized non-performance carriers need to be shut down and credited into the carrier bank. We propose a derived threshold for good carrier utilization and...

Multiband applications can be realized as a result of designing a double U-slot rectangular patch antenna. CST Microwave Studio software was used to design the microstrip antenna with a transmission line feed and simulate return loss and radiation patterns. The antenna was fabricated in-house using a printed board CNC machine and was measured and c...

Customer migration to other operators is mainly triggered by lack of coverage and poor technical service with a consequence of threatening annual profit returns. We propose a new comprehensive standard for in-building penetration loss through outer walls in Palestine and vast areas in the Middle East at 900 MHz and 2.4 GHz frequency bands. The mode...

Countries in the Mediterranean region able to benefit from the IP-based Euro-Mediterranean (EUMED-CONNECT) network project are Algeria, Cyprus, Egypt, Israel, Jordan, Lebanon, Malta, Morocco, the Palestinian authority, Syria, Tunisia and Turkey. In Palestine, the project seeks to establish an academic network with a 45 Mbps bandwidth capacity which...

The results of a study to evaluate current design criteria assumptions for PCS/MMDS (1.9/2.5 GHz band) wireless networks and how they relate to in-building coverage are reported. The analysis focuses on the actual signal density levels required on the outside of most buildings to penetrate and provide adequate service within the buildings. External...

Core Radio Frequency (RF) Engineering is a department within Sprint: a national telecommunications corporation that is responsible for the design, planning and network operation for sustained coverage, capacity and optimization. It coordinates efforts with the regional field engineering departments for meeting those objectives. Core RF Engineering...

We present a model to derive MMDS/ISM band correlation path losses from collected PCS band experimental data. The model is based on experimental data taken in several suburban areas using combined mode portable PCS and MMDS CW transmitters. The characterization used is a linear curve fitting the decibel path loss to the decibel-distance, with a Gau...

Core RF Engineering at Sprint has completed a study to assess current design criteria assumptions for PCS wireless networks and how they relate to in-building-coverage. This analysis focused on the actual signal density levels required on the outside of most buildings to penetrate and provide adequate service within the buildings. Core RF modeled e...

Co-channel interference (CCI) from other reuse cells restricts the channel capacity of cellular communication systems. In fixed wireless access systems, the deployment of directional antennas at the customer premises equipment (CPE) that point towards their base stations suggest a direct and easy method to combat CCI and enhance capacity in a line-...

Linearisation of a radio basestation amplifier using a third order, a fifth order and a seventh order predistortion scheme is studied. Adaptive predistortion using a third order predistorter improved the amplifier intermodulation distortion (IMD) by between 6.4 dB and 33 dB from the third IMD power level (i.e., maximum power amplitude variation of...

Most cellular systems provide for the use of transmitter power control to reduce co-channel interference for a given channel allocation. Efficient interference management aims at achieving acceptable carrier to interference ratios (CIR) in all active communication links within the system. This paper is a study of the effect of decreasing the power...

Linearisation of a radio basestation amplifier using a third order and a fifth order predistortion scheme is studied. Adaptive predistortion using a third order predistorter improved the amplifiers intermodulation distortion by between 6.5 dB and 30 dB as measured by a two-tone test. The variation in improvement is due to changes in the input power...

The linearisation of a radio basestation amplifier using a third order and a fifth order predistortion scheme is studied. Adaptive predistortion using a third order predistorter improves the power level of the inter-modulation distortion (IMD), which results from amplitude and phase nonlinearities in the amplifier frequency response, by between 6.5...

Most cellular radio systems provide for the use of transmitter power control to reduce co-channel interference for a given channel allocation. Efficient interference management aims at achieving acceptable carrier to interference ratios (CIR) in all active communication links within the system. This paper is a study of the effect of decreasing the...

A finite difference method is used to design a new type of sectoral horn antenna with corner channel inserts which produces a tapered aperture amplitude distribution in the E-plane. The channel inserts, which present a simple modification to the horn aperture geometry, act as effective side-lobe suppression devices. The efficiency of the suppressio...

The authors introduce two design strategies for microwave component design. These are optical ray tracing and a numerical solution to the electromagnetic problem by a finite difference scheme. Both techniques are applied to the design of E-plane sectoral horn antennas and quasi-optical microwave components based on dielectric waveguides. The relati...

Deviation from plane wave conditions within the ultrasound beam of a Doppler blood flow detector leads to a non-linear relationship between the phase angle of the back-scattered signal and the scatterer position. This in turn leads to frequency modulation of the Doppler signal and an increase in the Doppler spectrum width. The relationship between...

Two distinct design methods for producing a tapered amplitude distribution across the E-plane aperture of a sectoral horn antenna are described and compared. The first system studied is essentially a lens in which the refractive index varies in a direction orthogonal to the axis. The authors refer to the horn as a `HYSEC' horn. The design lends its...

Optical ray theory is used to design a phase-corrected microwave horn antenna of short-length which produces a tapered aperture amplitude distribution in the E-plane. The basis of the design is the creation of a region where the effective refractive index varies with hyperbolic secant (HYSEC) form in a direction normal to the horn axis. In a practi...

A finite-difference method is used to design a sectoral horn antenna that uses corner channel inserts to produce a tapered aperture amplitude distribution in the E-plane. The channel inserts effectively suppress sidelobe levels in the radiation pattern. Good agreement is found between predicted and experimental far-field distributions.

A new design on ray theory is presented for a phase corrected horn antenna which is shorter than one with a hyperbolic secant refractive index profile. A dielectric load is essential for realistic implementation. With load permittivity decreasing linearly towards the aperture, a smooth flared profile can be obtained. The antenna's compactness makes...