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A sudden geometric increase in population of Akoko North West Local Government Area of Ondo State has led to an increase in demand for water and harnessing of subsurface water reserve. A total of twenty six water samples obtained from both boreholes and hand-dug wells were analyzed for their physico-chemical characteristics with the aim of assessing their quality, usability and also to determine the level of their contamination in the local government which is dominated by granite gneisses, charnockites, and augen gneisses as the main rock types. The following physico-chemical properties were analyzed for in the samples collected: electrical conductivity (EC), pH, total alkalinity (TA), total dissolved solids (TDS), total suspended solids (TSS), acid neutralizing capacity (ANC) with major cations (Na + , Mg 2+ , Ca 2+ ), anions (PO4 3- , HCO3 - , SO4 3- ) and several heavy metals (Zn 2+ , Fe 2+ , As + , Ni + , Pb 2+ , Cd + , Cu 2+ ). The following results were obtained from the analysis: Zn 2+ (0.109 – 0.437 ppm), Fe 2+ (0.216 – 0.726 ppm), As + (0.01 – 0.03 ppm), Ni + (0.036 – 0.074), Pb 2+ (0.003 – 0.010), Cd + (0.002 – 0.007), Cu 2+ (0.086 – 0.241) with appreciable abundances of PO4 3- , Cd + , Fe 2+ and Ni + some exceeding while some others are below the WHO acceptable level for drinking water, thereby making it a serious source of concern as it indicates varying levels of faecal contamination (from leaky septic tanks, interception with pit latrines) and heavy metal liberation into the water consumed by the residents. It was also noticed that the water was fresh based on the analysis of the Total Dissolved Solids and the Pb 2+ concentrations almost exceeded the standard permissible limit. Generally, it was concluded that the overall quality of the ground water is averagely good physico-chemically.

In this paper, various architectures of three-dimensional compact microwave balanced to unbalanced (balun) transformers for Bluetooth/WiFi antenna applications are successfully designed and optimized using the design of experiments (DOE) approach. Two different multilayer topologies, one microstrip and one stripline, are investigated on low temperature co-fired ceramic (LTCC) substrate. The design goals for both baluns are perfectly balanced outputs from 2 to 3 GHz and a resonant frequency of exactly 2.4 GHz. It is demonstrated, using only eight simulations, that perfectly balanced outputs are not possible under the given conditions in the case of the microstrip balun. Nevertheless, the stripline balun can be optimized due to its almost symmetrical structure, and both simulations and measurement results verify the conclusions. The DOE method is very simple to implement and gives a clear understanding of the system behavior at the beginning of the design process, reducing the amount of work required for achieving the design goals by orders of magnitude compared to the widely used trial-and-error approach. The matching and unique measurement issues regarding the calibration, placement of probes and the de-embedding of the microstrip to coplanar waveguide transitions are discussed in detail for the optimized stripline balun. This technique can be easily applied to the fast and efficient optimization of complicated radiation structures, such as reconfigurable or multilayer multiband antenna arrays.

In this paper an antenna is presented that satisfies the two-fold radiation pattern requirement of communication systems utilizing both geostationary satellites and terrestrial transponders for coverage of mobile terminal away from the equator. A typical requirement for such a system is a low profile antenna that maximizes left-hand circularly polarized radiation in the satellite viewing angle, from 30/spl deg/ to 70/spl deg/ from zenith, and vertically polarized radiation in the terrestrial station viewing angle, from 70/spl deg/ to 90/spl deg/ from zenith. This dual radiation pattern coverage is achieved by integrating a small four arm spiral with a top loaded monopole into a single compact volume, an antenna termed a spirapole.

Future wireless communications systems require better performance, lower cost, and compact RF front-end footprint. The RF front-end module development and its level of integration are, thus, continuous challenges. In most of the presently used microwave integrated circuit technologies, it is difficult to integrate the passives efficiently with required quality. Another critical obstacle in the design of passive components, which occupy the highest percentage of integrated circuit and circuit board real estate, includes the effort to reduce the module size. These issues can be addressed with multilayer substrate technology. A multilayer organic (MLO)-based process offers the potential as the next generation technology of choice for electronic packaging. It uses a cost effective process, while offering design flexibility and optimized integration due to its multilayer topology. We present the design, model, and measurement data of RF-microwave multilayer transitions and integrated passives implemented in a MLO system on package (SOP) technology. Compact, high Q inductors, and embedded filter designs for wireless module applications are demonstrated for the first time in this technology.

A sudden geometric increase in population of Akoko North West Local Government Area of Ondo State has led to an increase in demand for water and harnessing of subsurface water reserve. A total of twenty six water samples obtained from both boreholes and hand-dug wells were analyzed for their physico-chemical characteristics with the aim of assessing their quality, usability and also to determine the level of their contamination in the local government which is dominated by granite gneisses, charnockites, and augen gneisses as the main rock types. The following physico-chemical properties were analyzed for in the samples collected: electrical conductivity (EC), pH, total alkalinity (TA), total dissolved solids (TDS), total suspended solids (TSS), acid neutralizing capacity (ANC) with major cations (Na+, Mg2+, Ca2+), anions (PO4³-, HCO3-, SO4³-) and several heavy metals (Zn2+, Fe2+, As+, Ni+, Pb2+, Cd+, Cu2+). The following results were obtained from the analysis: Zn2+ (0.109 - 0.437 ppm), Fe2+ (0.216 - 0.726 ppm), As+ (0.01 - 0.03 ppm), Ni+ (0.036 - 0.074), Pb2+ (0.003 - 0.010), Cd+ (0.002 - 0.007), Cu2+ (0.086 - 0.241) with appreciable abundances of PO4³-, Cd+, Fe2+and Ni+ some exceeding while some others are below the WHO acceptable level for drinking water, thereby making it a serious source of concern as it indicates varying levels of faecal contamination (from leaky septic tanks, interception with pit latrines) and heavy metal liberation into the water consumed by the residents. It was also noticed that the water was fresh based on the analysis of the Total Dissolved Solids and the Pb2+ concentrations almost exceeded the standard permissible limit. Generally, it was concluded that the overall quality of the ground water is averagely good physico-chemically. Um aumento geométrico e repentino da população da área de Akoko North West do Governo Local do Estado de Ondo levou a um aumento pela procura de água e aproveitamento de reserva de água subterrânea. As características físico-químicas de vinte e seis amostras de água obtidas de poços perfurados e cavados à mão foram analisadas com a finalidade de avaliar sua qualidade, usabilidade e determinação de seu nível de contaminação na área do governo local, que é dominado principalmente pelas rochas de granito, gnaisses, charnockitos e augen gnaisse. As seguintes propriedades físico-químicas das amostras coletadas foram analisadas: condutividade elétrica (CE), pH, alcalinidade total (AT), sólidos totais dissolvidos (TDS), sólidos suspensos totais (SST), a capacidade de neutralização de ácido (CNA), com os principais cátions (Na+, Mg2+, Ca2+), ânions (PO4³-, HCO3-, SO4³-) e vários metais pesados (Zn2+, Fe2+, As+, Ni+, Pb2+, Cd+, Cu2+). Os seguintes resultados foram obtidos: Zn2+ (0,109 - 0,437 ppm), Fe2+ (0,216 - 0,726 ppm), As+ (0.01 - 0.03 ppm), Ni+ (0,036 - 0,074), Pb2+ (0,003 - 0,010), Cd+ (0,002 - 0,007), Cu2+ (0,086 - 0,241), com concentrações apreciáveis de PO4³-, Cd+, Fe2+e Ni+ algumas superiores, enquanto outras abaixo do nível aceitável da WHO para água potável, fato que se constitui em grande preocupação, pois indica níveis variáveis de contaminação fecal (de vazamento de fossas sépticas e de latrinas) e contaminação de metais pesados na água consumida pelos moradores. Também foi observado que a água era doce com base na análise dos sólidos totais dissolvidos e que as concentrações de Pb2+quase ultrapassaram o limite padrão estabelecido. Observou-se que a qualidade físico-química global da água do solo é medianamente boa.

The successful use of the design of experiments (DOE) approach in an optimization feasibility study for two microwave balanced to unbalanced transformers (baluns) is presented. The medium of interest is the multi-layer low temperature cofired ceramic (LTCC) and two different topologies, one microstrip and one stripline, are investigated. The design goals are perfectly balanced outputs from 2-3 GHz and a resonant frequency of exactly 2.4 GHz. It is demonstrated, using only eight simulations, that perfectly balanced outputs are not possible under given conditions in the case of the microstrip balun. Nevertheless, the stripline balun can be optimized due to its almost symmetrical structure, and both simulations and measurement results verify the conclusions. The DOE method is very simple to implement and gives a clear understanding of the system behavior at the beginning of the design process, reducing the amount of work required for achieving the design goals by orders of magnitude compared to the widely used trial-and-error approach.

The multi-resolution time domain technique is applied to the modeling of multilayer packaging structures. In particular, the performance of a multilayer balun is evaluated using MRTD and the results are compared to those obtained using the FDTD technique as well as a commercial simulator. The abilities of MRTD to handle complex structures and as nonuniform cells are highlighted.

We present the development of an integrated Bluetooth transceiver module using a commercial low temperature co-fired ceramic (LTCC) process. The developed module contains a power amplifier (PA), low noise amplifier (LNA), mixer, balun, band select filter and integrated antenna. The MMICs and passives are developed using a commercial 0.24 /spl mu/m CMOS process and LTCC respectively. The power amplifier is capable of providing an output power of 20 dBm for the Bluetooth class 1 specification. To the best of our knowledge, this work presents the first report of module with integrated antennas.

A highly integrated transceiver module for 5.8 GHz OFDM communication system is presented. The antenna and filter are directly fabricated on the module using multi-layer packaging technology in order to reduce size and interconnection losses. A cavity backed patch antenna with a vertical feed and an embedded 3D filter have been designed and integrated on the package using a low-temperature cofired ceramic (LTCC) process. RF functional blocks including PA, LNA, mixers and VCO are developed using GaAs-based MMICs and are attached on the surface of the LTCC board. RF blocks are vertically stacked and connected through via structures. The specifications of the functional blocks have been determined and verified through system simulations based on the IEEE 802.11a standard. The total size of the module is 14/spl times/19/spl times/2 mm/sup 3/. Measurement and simulation results of the components and the module are also presented.

The integration of an antenna with an RF module is an attractive solution for realizing a small size and low cost wireless transceiver. Multi-layer planar antennas for system-on-a-package (SOP) application are presented. Two different types of antennas for the low temperature co-fired ceramic (LTCC) package and the multi-layer organic (MLO) package are developed. For the LTCC package, the cavity-backed patch antenna has been developed, in order to increase bandwidth and to reduce the size of the ground plane. A via feed is used for direct connection with other RF blocks. For the cavity backed patch antenna, bandwidth is increased by 20% and real estate including ground plane is reduced by 50%, compared to the conventional patch antenna. For the MLO package, a lifted slot antenna has been developed. In order to reduce loss at feeding point and to minimize pattern distortion, via feed has been used. The antenna has been designed at 5.8 GHz and has gain of 3.7 dBi and bandwidth of 14%.

Presents the design, and measurement of RF-microwave multilayer interconnects and integrated passives implemented in a fully-organic system on package(SOP) technology. A CPW-microstrip interconnect scheme demonstrates a measured insertion loss of 1.7 dB at 12 GHz and a return loss better than 20 dB to 12 GHz. The novel hollow ground plane inductor configuration exhibits Q and effective inductance(Leff) enhancement by a factor of 2.5 and 2, respectively with SRF to 14 GHz. In addition, compact filters have also been designed for Optical Sub-Carrier Multiplexing(OSCM) link applications. These developments suggest the feasibility of building highly integrated organic-based radio front-end SOP.

This paper presents the development and characterization of compact and highly integrated microwave and millimeter wave radio front-end Systems-on-Package (SOP). The three-dimensional transceiver front-end SOP architectures incorporate on-package integrated lumped element passives as well as RF functions primarily filters, baluns, and antennas in standard multi-layer LTCC and fully-organic technologies. An LTCC-based 14 GHz transmitter for satellite outdoor unit, an OC-192 transmitter incorporating Ku-band Optical Sub-Carrier Multiplexing (OSCM) technique as well fully-organic SOP transmission lines and lumped-element components have been demonstrated. These prototypes suggest the feasibility of developing highly miniaturized cost-effective SOP transceivers applicable not only for wireless but also for optoelectronics links.

We present the development, implementation and measurement of a 3D-deployed RF front-end System-on-Package (SOP) topology in a standard low-loss multi-layer ceramic (LTCC) technology. A compact 14 GHz GaAs MESFET-based satellite transmitter integrated with a low-loss embedded filter for outdoor units were built on a 400 × 310 × 35.2 mil 3 943AT tapes. The LTCC stripline filter exhibits a measured maximum insertion loss of 1.8 dB while the entire transmitter chain yields a 32-34 dB of gain in the 13.5 to 14.5 GHz range. These results suggest the feasibility of building highly SOP integrated microwave and millimeter wave radio front ends. In addition, a highly integrated transceiver module for OFDM Communication System using Multilayer Packaging technology as well as Multilayer Integrated Passives using Fully Organic SOP technology demonstrate the capabilities of SOP for other applications such as the OFDM Wireless LAN and LMDS.