Qualifications, Experience, and References

As a consulting engineering firm, our customer satisfaction is indicated by the number of clients who return to us for additional work after completion of an initial project. We have clients for whom this firm has been doing work since the 1940s. Ninety percent of our non-competitive work is for repeat customers, or for customers who have been referred by our existing clients or by their attorneys.

The following projects were performed by Hatfield & Dawson engineers and are listed here to illustrate the specific ways in which Hatfield & Dawson meets client objectives by our electromagnetic energy measurement, telecommunications engineering, and FCC regulatory background skills. Hatfield & Dawson is unique among telecommunications engineering firms in that our normal practice includes representation of clients in broadcasting, land mobile, government communications, and other types of telecommunications uses. The result of this breadth of work experience is that we are efficient, innovative, experienced, and skilled in resolving problems that result from potentially incompatible electronic uses. Combined with our experience in resolving non-ionizing radiation problems, these unique capabilities allow us to ameliorate old problems and design new problem-free facilities for our clients.

  • Analysis and Measurements; Multi-use, Two-way Radio Site; Arlington County, VA
    Previous non-ionizing radiation measurements and calculations made by another firm were so flawed that they were shown to be in error by citizens raising objections to the project during the land use approval process. Hatfield & Dawson made correct calculations and extensive measurements, and met with local citizens to show the negligible impact of the project. Our efforts satisfied the neighborhood's objections. The project was completed in 1992.

    Project engineer: Jim Hatfield
    Client reference:
    Lisa Thompson, Arlington Co. Emergency Communications Center
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  • Interference and Compatibility Analysis/Recommendations; U.S. West Vector Group, Inc.; Aurora, CO
    Hatfield & Dawson was retained by U.S. West New Vector Group, Inc., to determine the source(s) of existing interference to the City of Aurora's 800 MHz Public Safety mobile radio system and to determine the mutual compatibility of U.S. West's proposed Horseshoe cellular radio cell site and the Aurora public safety facilities. The cell site and the public safety radio system antennas were to be separated by about 1,300 feet.

    The City of Aurora system had previously received repeated sporadic interference that apparently was related to operation of mobile cellular telephones near its repeater or satellite receiver sites. After the interference problems were observed, and before the measurements or analysis shown in this report were performed, the City took appropriate corrective measures to protect its system from this interference. The analysis contained in Hatfield & Dawson's report was prepared to evaluate the potential for any new interference to either the City of Aurora system or the proposed U.S. West cell site and to ensure that both systems could operate in close proximity without detrimental effects on either system.

    To determine the potential for interference resulting from operation of the Horseshoe cell site, a detailed intermodulation study was performed. The study was designed to determine the impact of the proposed U.S. West system on existing facilities at the City of Aurora repeater site and the impact of the existing facilities at the City of Aurora site on the proposed U.S. West system. The intermodulation study was based on the actual characteristics and physical configuration of the equipment at both sites.

    The study indicated that the likelihood of interference either to the City of Aurora system from the proposed cell site or to the proposed cell site from the City of Aurora system was extremely small. The cell site was constructed as planned, and both systems now operate without any mutual interference. This project was completed in 1994.

    Project engineer: Tom Eckels
    Client references:
    Oscar Granger, U. S. West
    Marty Bain, City of Aurora
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  • Mitigation of Blanketing Interference to Consumer Electronic Equipment; KVTI; Lakewood, WA
    On behalf KVTI(FM), a non-commercial educational FM Broadcast station licensed to Clover Park Technical College in Tacoma, Washington, Hatfield & Dawson carried out a program of interference mitigation, resolving more than 50 cases of interference to consumer electronics equipment ranging from VCRs and television sets to stereos, CD players, telephones, and boom-boxes. The interference occurred in residences within two miles of the KVTI transmitting antenna located on the grounds of a local high school and close numerous single-family houses. Before receiving its license from the Federal Communications Commission (FCC), KVTI had to satisfy all complaints regarding interference caused by its high power signal during its first year of operation, and establish an ongoing information program designed to assist residents in resolving interference complaints after the initial one-year period.

    Hatfield & Dawson resolved the initial complaints and filed a detailed report with the FCC describing how interference was eliminated for each piece of equipment in each household. As a result of interference resolution work and the report, the FCC granted the station a license in 1996. We also provided Clover Park Technical College with a handbook and other information sheets that showed how to install filters and ferrite cores on consumer equipment to eliminate the effects of the blanketing interference. These materials continue to be used by the College to assist in the ongoing resolution of new interference complaints. This project was completed in 1995.

    Project Engineers: Steve Lockwood and Tom Eckels
    Client reference:
    John Mangin, General Manager, KVTI (FM)
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  • Technical Analysis for Land Use Ordinance Development; City of Seattle Office of Long-Range Planning; Seattle, WA
    As part of a comprehensive rewrite of land use ordinances and regulations for communications facilities, Hatfield & Dawson prepared background studies and analysis. We conducted extensive measurements of existing levels of non-ionizing radiation, made recommendations for local ordinance standards for radio-frequency energy density, and assisted in preparation of the environmental impact statement for the resulting ordinance. This project was completed in 1989. Hatfield & Dawson continues to provide technical assistance to assist the City's planning agency in both general and specific case telecommunications site land use questions through an indefinite delivery contract that is renewed annually. We also perform specification, design, and NIER analysis for specific City of Seattle communications sites associated with the City's 800 MHz trunked communications system.

    Project Engineer: Ben Dawson
    Client References:
    Cliff Marks, Office of Long Range Planning
    Teresa Rodriguez, ESD Facility Services
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  • Intermodulation and NIER Measurements; Bureau of Land Management (BLM); East Butte, ID
    East Butte is a prominent feature of the landscape northwest of Pocatello, Idaho, on the eastern edge of the Idaho National Engineering Laboratories restricted access zone. The Pocatello office of the Bureau of Land Management has managed it as a communications site since the 1950s or earlier. In the intervening years a very large number of users of all types have become licensees/tenants of the BLM. In early years, facility management did not consider various needs for electromagnetic compatibility among the great variety of users. Some users of the site experienced difficulty in systems operations due to real or perceived effects of their neighbors' systems.

    As a result of the BLM effort to develop a site manual for management of multiple use sites such as East Butte, the BLM Pocatello office arranged to have the site users contract with Hatfield & Dawson for a comprehensive set of site characterization measurements. This included non-ionizing electromagnetic radiation (NIER) measurements for safety evaluation and recommendations for resolving intermodulation and other electromagnetic compatibility problems at the site. Although not all of our recommendations were implemented, the project resulted in reduced levels of electromagnetic incompatibility. This project was completed in 1993.

    Project Engineer: Tom Eckels
    Client reference:
    Len Stears, BLM Communications Site Manager (now retired)
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  • Intermodulation and Electromagnetic Incompatibility Analysis; Idaho National Engineering Laboratory (INEL); East Butte, ID
    The INEL proposed to install a new 20-channel, trunked 400 MHz radio system at East Butte. Because this site is so heavily used, there were concerns about intermodulation and electromagnetic incompatibility from the proposed operation. The INEL contractor, EG&G Idaho, contracted with Hatfield & Dawson to conduct a complete analysis of these potential effects. Our report demonstrated some minor effects that required attention, but indicated that the proposed system would operate satisfactorily and without adversely impacting any pre-existing users. This project was completed in 1992.

    Project Engineer: Tom Eckels
    Client reference:
    Wayne Ridgway, INEL
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  • Towers and Antenna System Inspections; U. S. Coast Guard; CA, MT, NV, OR, and WA
    Hatfield & Dawson was part of the TRA Tower Engineering team that performed the FY93 tower inspection program for the U.S. Coast Guard. This project included field inspection and minor maintenance on 110 towers located in California, Montana, Nevada, Oregon, and Washington. The towers range in height from 20-foot self-supporting microwave towers to 700-foot guyed towers and include low frequency LORAN and very low frequency LORAN-C sites. The inspection team consisted of engineers from TRA Tower Engineering, personnel from a tower engineering company, and Hatfield & Dawson. We performed complete electrical inspections of the antenna systems and measured non-ionizing radiation levels of the antenna facilities and, in most cases, the transmitting equipment. In instances where the analysis showed levels above accepted standards, recommendations were made for amelioration. We also conducted a set of NIER measurements at the Coast Guard shortwave transmitting site near Bolinas, CA, and provided the Coast Guard with a specialized non-ionizing radiation safety training class for their communications technicians and engineers who are responsible for these communications sites. This project was completed in 1994.

    Project Engineer: Jim Hatfield
    Client reference:
    Phil Lewis, PE, U.S. Coast Guard
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  • NIER Studies; Fisher Broadcasting Company; Seattle, WA
    Hatfield & Dawson acted as a consultant to KOMO (Fisher Broadcasting) for measurements of radiation levels on Queen Anne Hill, Seattle. This facility is located in close proximity to towers used by three other television stations, as well as facilities for land mobile and microwave use operated by the City of Seattle, Boeing Company, and various communications common carriers. We have made measurements at this sites of KOMO, KIRO, and KING.

    Project Engineer: Jim Hatfield
    Client reference:
    Donald Wilkinson, PE, Director of Engineering, Fisher Broadcasting Co.
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  • Measurement and Analysis of RF Shock and Burn Hazard, Makalapa-Iwilei, at 138 kV Transmission Line; Hawaiian Electric Company; Honolulu, HI
    Hatfield & Dawson determined levels of radio-frequency energy from multiple frequency high power AM transmitter sites induced in an adjacent 138 kV transmission line. This project included contact current measurements, as well as calculated values of induced current in the transmission line conductors. The analysis results were the basis for a series of recommendations for work practices and amelioration of RF shock and burn hazards. This project was completed in 1996.

    Project Engineer: Jim Hatfield
    Client reference:
    Warren Hayakawa
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  • Cellular Site Engineering Certifications; US West-New Vector and Cellular One; King County, WA
    Some local government land use authorities have adopted maximum non-ionizing radiation exposure analysis requirements as a pre-condition for site use approval. In King County, all new communications site facilities require such analysis as a part of the land use approval process. Hatfield & Dawson has been retained by various cellular and PCS providers to calculate NIER in land use applications for various counties and municipalities. These providers include AirTouch, AT&T Wireless, Nextel, Sprint, GTE, Western Wireless, PageNet, and others. These projects have also included the measurements of electromagnetic fields around base stations to meet local land use requirements. Calculations and/or measurements have been made for more than 250 sites. In addition, US West-New Vector, Sprint Spectrum, and AT&T Wireless engaged us to analyze the electromagnetic compatibility of new cell site structures with pre-existing nearby medium wave antenna systems. Our expertise in mathematical modeling of medium wave (as well as LF and HF) antennas has allowed us to assure continued maintenance of critical operating conditions for these antennas in the presence of substantial reradiation effects. These projects are ongoing.

    Project Engineers: Steve Lockwood, Dave Pinion
    Client Reference:
    Oscar Granger, US West-New Vector
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  • Co-Site Interference and Feasibility Study; Denver International Airport; Denver, CO
    This extensive project illustrates Hatfield & Dawson's ability to provide solutions to complex telecommunications engineering problems in an environment of many users and conflicting requirements. Hatfield & Dawson was retained by a consortium of cellular and PCS providers and by Denver International Airport to perform a detailed co-site interference study and to make recommendations with respect to the location of proposed cellular and PCS sites at DIA. The purpose of the study was to assure that the cellular and PCS sites would provide optimum coverage of the DIA complex (including underground areas) without causing interference to existing DIA and tenant UHF, 800 MHz, and 900 MHz two-way radio systems. Hatfield & Dawson's involvement in this project is ongoing, and includes supervision of the cellular and PCS sites on behalf of DIA.

    Hatfield & Dawson
    • Established coverage and capacity requirements within the DIA complex for present DIA Public Safety and Tenant users, for three providers of Cellular or similar services (AirTouch, AT&T Wireless, and NEXTEL), and up to six providers of PCS services.
    • Performed a detailed survey of the site to determine the location and configuration of all existing and proposed radio systems at the airport and established the present coverage provided by existing 800 MHz and Cellular systems.
    • Determined the potential for interference to any of the existing Public Safety/Tenant systems as a result of the operation of the proposed systems.
    • Analyzed the proposed facilities to determine compliance with applicable standards with respect to human exposure to non-ionizing electromagnetic radiation.
    • Provided an analysis of the existing RFDS (Radio Frequency Distribution System), which provides radio coverage to underground areas and the parking garages at DIA, and an evaluation of its potential for use by the Cellular and PCS carriers to provide coverage inside DIA facilities.
    • Developed a site plan for DIA that will specify appropriate locations for repeater sites and cell sites used for each of the systems analyzed to allow future expansion of cellular and PCS systems not already studied in this report.
    • Developed a set of site standards, including requirements for antenna locations for specific systems, requirements for receive and transmit isolation and filtering, and effective radiated power limits.
    • Performed a detailed interference analysis and provided recommendations for a temporary cell site for AT&T, AirTouch, and NEXTEL that provided improved cellular coverage at DIA for the Summit of the Eight conference in April 1997 and interim coverage improvements pending installation of the long-term DIA cell site.
    • Made recommendations with respect to the final location and configuration of the cellular and PCS sites that allowed the providers to work with DIA to implement appropriate facilities.

    Project Engineers: Tom Eckels, Dave Pinion
    Client references:
    Jim Winston, Denver International Airport
    Gail Klapper, Esq., The Klapper Firm (U.S. West attorney representing communications carriers)
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  • United Airlines Ground Radio System In-Building Coverage System; San Francisco International Airport; San Francisco, CA
    This project involved an initial site survey with extensive indoor and outdoor field strength measurements. The purpose of the survey was to establish the present levels of indoor and outdoor coverage for the UHF ground radio system operated by United Airlines and to establish the best location for a new base station repeater site for that system.

    The measurements were also used to determine requirements for an in-building coverage enhancement system in the new International Terminal Building and in Concourse G. Both the new terminal and the new concourse are Common Use Terminal Equipment facilities shared by a number of airlines.

    H&D has provided specifications for the new in-building coverage system, and will supervise system installation and perform performance tests once the system is completed.

    Project Engineers: Tom Eckels, Tom Gorton
    Client Reference:
    Michael Lunebach, United Airlines
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  • King County Comprehensive Radio Plan; Seattle, WA
    As part of a Comprehensive Radio Plan the team of H&D and Frank Thatcher Associates performed a complete analysis of King County's wireless communications needs, present wireless systems and technologies, future systems and technologies available to meet the County's needs, the potential for re-allocation of the County's existing spectrum, and the potential impact of FCC regulations and international agreements on the County's wireless systems.

    The study produced by H&D/FTA included
    • An inventory of the County's current wireless communications systems and spectrum resources, and an overview and assessment of the County's wireless communications needs.
    • An analysis of regulatory actions by the FCC, and an assessment of how those changes will affect the County's wireless communication systems and environment over the next decade.
    • A catalog of viable technology options available to the County, including an assessment of their potential costs, advantages and disadvantages, and recommendations on the appropriateness of those technologies, given scope of the County's communications needs identified by the project.
    • Recommendations on the continued use of existing systems, potential design criteria for new systems, and policies or procedures that should be implemented by the County to ensure effective spectrum resource management in the future.

    Client Reference:
    Dan Overgaard
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  • Interlink Network Corporation/Formosa TV; Taiwan
    In 1996 Interlink Network Corporation engaged Hatfield & Dawson to provide it with assistance in evaluating the commercial feasibility of establishing a new television network in Taiwan, primarily using transmission on channels 5 and 6. The technical evaluation included a study of the necessary television signal strengths for NTSC signals on these channels to provide competitive service in the Taiwan environment. The process included a theoretical analysis of necessary signal strength at typical receiver locations, as well as extensive testing of typical Taiwanese receiving antennas (designed for high band channels 7 - 13) for antenna gain and pattern on channel 5. In addition, the possibility of destructive interference from PAL television operations in mainland China, only 200 kilometers distant across Taiwan Strait, was evaluated. This was accomplished by a theoretical analysis of the interference mechanism and desired/undesired signal levels, together with extensive measurements of actual received signals from mainland China.

    Subsequent to the implementation of service by Formosa TV, in 1997 we were requested to make recommendations for improvement of service. All of the transmitting sites were inspected, and a series of measurements of transmitter performance and signal strength were made. The resulting recommendations were incorporated in a comprehensive report.

    Client Reference:
    Trong R. Chai, Formosa Television
    886.2.5702570 (Taiwan)
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  • Intel Corporation Vertical Blanking Interval (V.I.) Data Transmission Analysis
    In 1995 Hatfield & Dawson, working with Intel engineering personnel, produced a comprehensive analysis of the requirements for successful data transmission using the Vertical Blanking Interval of standard NTSC television signals. The analysis included extensive measurement of the signal level and bit error rate of derived V.I. data as transmitted over the air by operating television stations and their translators, as well as through cable television and master antenna distribution systems. In addition, a series of propagation predictions and maps of predicted data were generated to demonstrate the inadequacy of standard FCC methods for reliable signal strength and data transmission prediction. These predictions used various techniques derived from Longley-Rice, et al, and others, weighted by measurement results.

    Client Reference:
    Al Kinney
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  • DirecTV Signal Strength Calculations and Mapping
    DirecTV in 1997 requested that Hatfield & Dawson prepare field strength maps of a television station signal in numerous zip codes well within the FCC method grade A contour. H&D obtained computer databases containing zip code data, and wrote programs to make the zip code data compatible with the mapping feature of signal strength prediction software. The resulting maps demonstrate the areas within each zip code that receive Grade B, Grade A, and better than Grade A service. This project required significant software development effort in a very short period of time, since none of the commercially available propagation software vendors provide the necessary programs.

    Client Reference:
    Bob Plummer
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  • Ambient RF Noise and Spurious Signal Levels in the 26.96-27.28 MHz ISM Band in Typical Home and Office Environments
    Hatfield & Dawson performed detailed measurements of the RF noise and spurious signal levels in the 27 MHz ISM band on behalf of a client interested in using this band for close range wireless interfacing of computer peripherals. Our study characterized noise and spurious signals emitted by VGA computer monitors and industrial equipment (including high power RF heat sealers) operating in this band. Measurements were made in both office and home environments in order to provide a complete characterization of the areas in which the proposed wireless equipment was intended to operate. We produced a complete report that showed the measurement results, and made recommendations with respect to the use of this band for the client's intended application.

    Client Reference:
    Dr. James Landsford
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  • City of Everett and Snohomish County Public Safety Agencies; March, 1997
    H&D prepared a complete application package for 17 NPSPAC 800 MHz public safety radio channels in Snohomish County, filed by the City of Everett on behalf of the public safety agencies of Snohomish County. The application included all forms required for filing with the FCC, as well as all exhibits required by the Region 43 NPSPAC Review Committee, for eleven simulcast repeater sites and five conventional sites. Detailed coverage predictions were provided for each site, and composite system coverage maps showing mobile, portable, and in-building predicted coverage were included in the application. The application included a system conceptual design limiting radiation in the direction of Canadian territory from each site, as required by the U.S.-Canada 800 MHz treaty.

    Client reference:
    Ray Stephanson, City of Everett, Mayor's Office
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  • Snohomish County Enhanced 9-1-1 Governing Board; June, 1995
    H&D prepared a study to respond to specific concerns raised by twelve rural Fire Districts regarding the coverage, cost, compatibility, and control of a proposed county-wide 800 MHz radio communications system. The final report included detailed analysis of, and responses to, each issue of concern to the rural fire chiefs, as well as a detailed set of propagation studies comparing the predicted coverage of the existing VHF radio system in Snohomish County to the predicted coverage of the proposed 800 MHz radio system.

    Client reference:
    Dan Prinz, Everett Police Department
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  • City of Everett, WA; March - September 1995
    In this project, H&D evaluated the City of Everett's existing radio system, prepared an analysis of alternatives for modification or replacement of the system, and prepared a set of recommendations, including a recommendation of the most cost-effective alternative. Our work included
    • A complete review of three existing radio system studies to assure that these studies accurately represented the technical and operational characteristics of the radio systems currently operated by the City of Everett.
    • Evaluation of the City's present and future radio communications needs based on the contents of the existing studies and additional interviews with key City personnel.
    • Determination of the best alternative for the improvement or the replacement of the City of Everett's radio communications system, in light of FCC Docket 92-235 spectrum "refarming" issues, and the City's present and future communications needs.

    The final report included a detailed analysis of the advantages and disadvantages of six options, including budgetary figures, for modification and/or replacement of the existing radio system and a recommendation for the best alternative among these options. This was the implementation of an 800 MHz trunked radio system, and a separate 800 MHz conventional system for mobile data.

    Client reference:
    Mr. Bob Cooper, City of Everett Dept. of Parks and Recreation
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  • Options for Housing Authority Radio System; City of Everett, WA; September 1995 - January 1996, The goal of this project was for H&D to determine the options for moving the radio operations of the Everett Housing Authority from its current operating frequency pair at 807/852.5125 MHz to a different frequency or to a different radio system in order to allow the EHA 800 MHz frequency pair to be used for a new Mobile Data System to be implemented by the Snocom regional dispatch agency and the City of Everett. Five different options were considered in the analysis and report, including moving the EHA radio operations to a private ESMR system, and using existing NPSPAC channels on a temporary basis pending construction of a new trunked 800 MHz system. Detailed technical and cost evaluations were made of each practical option, and the final recommendation described the two most cost-effective options.

    Client reference:
    Mr. Bob Cooper, City of Everett Department of Parks and Recreation
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  • King County Water & Sewer Department Radio System Study; April 2000
    H&D performed a detailed analysis of two alternatives for providing an off-site two-way radio system to replace the existing VHF (150 MHz) simplex radio system used by the Wastewater Treatment Division (WTD) of the King County Department of Natural Resources. The existing single-channel two-site simplex VHF system operated by WTD did not meet the present coverage and operational needs of the agency, and could not meet the agency's needs for expanded coverage in southern Snohomish County, where a new treatment plant is planned.

    The report provided by H&D contained a thorough analysis of the two alternatives. The first alternative was an upgrade of the existing VHF system from simplex to repeater-based operation, the addition of an additional repeater site and voting receiver sites, and a new microwave interconnect system to replace the existing leased line interconnects. The second alternative was to use the King County Regional Trunked Radio System (KCRS), which provided both the needed coverage and a high-reliability microwave interconnect system. Based on a needs analysis, a detailed coverage comparison of the two systems, and a detailed economic analysis of the two alternatives, H&D recommended that WTD move to the KCRS.

    Client reference:
    Ken Alver
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  • City of Springfield Police Department, OR
    H&D first developed a conceptual plan for a new radio system for the City of Springfield Police Department, which now operates on several UHF repeated channels. We conducted a detailed survey of the existing system, and developed a needs analysis. We also developed computer-generated propagation maps to determine an optimum site for a new repeater station to improve radio coverage. In subsequent tasks, we developed technical specifications for a new radio system, and assisted the City in the procurement process. H&D assisted the City in continuing management of the project, and performed acceptance tests.

    Client reference:
    Bryan Van der Pool
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  • Port of Seattle Radio System Project; 1993
    The H&D/FTA Joint Venture partners, under Hatfield & Dawson project management, prepared a study of the existing radio communications systems operated by the Port of Seattle.

    A complete questionnaire was prepared in consultation with Port staff, and all departments of the Port were surveyed for radio use and future radio requirements. A survey of all radio system units and facilities was performed. Based on this information, a report was prepared, and conceptual radio communications system design recommendations were made. Because of the wide area coverage required and the requirement for portable coverage for Port Police inside buildings in the waterfront and airport areas, the system was designed to a very high level of performance and reliability.

    Subsequent to the system design and specification, the Port entered into discussions with other nearby political jurisdictions (City of Seattle, King County) regarding combined purchasing and the possibility of combined radio system operation. We assisted the Port staff in the analysis of the equipment purchasing, the possible joint activities with other political jurisdictions, and we monitored contractor performance.

    Client reference:
    Tina Soike, PE, Port of Seattle
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  • University of Washington Radio System Study and University Hospital "Lossy Line" Extension; 1993
    The University of Washington Telecommunications Department engaged H&D to study campus-wide two-way radio system needs, and to prepare a report on telecommunications services as a guideline for future planning by the Telecommunications department staff. The University, like many large institutions, did not have a good inventory of the systems in operation. We prepared a comprehensive questionnaire and interviewed major operating department heads and other UW personnel with particular communications requirements or technical expertise. From the interview material, we prepared the planning report required.

    Additionally, we performed a comprehensive survey of the "lossy line" distribution system in the University Hospital and Health Sciences buildings. This system uses radiating coaxial cable to distribute signals from two-way radio and paging radio base stations in the lower floors of the Health Sciences complex, where signal strength levels from radio system antennas on the building roof are inadequate. The system was constructed in a random, haphazard fashion over the years, and is not suitable for use at 800 MHz and higher frequencies. We performed a redesign of the hospital portion of the system, including supervision of the contractor's installation of the revised system. The revised system is fitted with wideband splitters, appropriate amplifiers, and some radiating antennas to provide more uniform signal strength in the lower floors of the hospital complex.

    Client reference:
    Ray Rickensrud, UW Telecommunications Director
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  • Washington State Patrol Facility Planning; 1990, 1996, 1997
    The Washington State Patrol operates a statewide telecommunications system. In addition to two-way radio base station operation, the system includes a high-reliability multiple loop microwave system.

    Relocations of several WSP regional headquarters required redesign of portions of this system. As a subcontractor to A & E firms responsible for the site and building design, H&D provided WSP with microwave network redesign options, cost analysis of alternatives, facility specifications, and support with land use and FAA negotiations. Because some portions of the microwave network were constructed before modern high reliability design standards were in use, the redesign options we provided resulted in upgraded operational reliability wherever possible. Our work included recommendations for new repeater and passive repeater locations at intermediate sites, and VHF propagation analysis for these new site locations.

    Together with a structural engineering subcontractor, H&D prepared a complete analysis of the existing radio site standards of the WSP and the Washington State Department of Transportation. These two agencies share many sites, but had conflicting practices and standards. H&D was engaged to review these standards, and to prepare a single set that met the objectives of both agencies.

    As a subcontractor to a computer consulting firm, H&D performed a study of the feasibility of consolidation of the communications and computer systems of the three Washington State transportation agencies, WSP, WSDOT, and the Department of Licensing. This study reviewed the two-way radio and microwave systems employed by the agencies, and investigated and identified areas of common interest and service requirement.

    Client reference:
    Pat Buller, WSP Supervising Communications Engineer
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