The greenfield project for wireless infrastructure is the creation of a new network on previously undeveloped space. In an unprecedented project of Vancouver, the goal was to plan, design, build, and commission an entirely new wireless network in a short time frame. Key project managers, engineers, acquisition, and construction specialists were assembled in realizing this ambitious goal.
I was one of the prime RF design engineers responsible for a large geographical area of Vancouver. I looked after RF planning and detailed design of the radio access layer. This entailed high level network design of site placement and cellular configuration to low level on-field surveys of construction sites. With reference to the link budget, the nominal site placement plan was established and zone search activity took place. I conducted site visits with site acquisition and construction specialists in determining suitable candidates that would best meet the nominal design. Deviation of nominal design would encounter a process of review that would conclude with client concurrence.
Upon identifying the site candidate, I proposed a site-level detailed RF design based on propagation, interference, and best-server simulations and compared against KPIs for specified clutter and zone boundaries. Construction drawings were generated of which I reviewed and RF qualified. Detailed build RF design was later specified after further optimization simulations. Parameters related to RNC definition of the cells were also determined such as NCELL and scrambling code definitions. The sites were eventually built and checked on-field for proper RF equipment configuration. To date, the target sites have been constructed to RF specifications.
December 11, 2009 – 7:36 pm
Manulife Centre is a prominent mall in downtown Toronto housing some of the finest shops in the city. This was one of many legacy GSM inbuilding systems that was upgraded to UMTS capabilities. I specified all of the RF-related civil work. This entail detailed specifications of all front-end coupling and an impact report of resulting antenna ERP as the per channel power would be constrained by the in-line BDAs and additional channels feeding the network. The front-end uses hybrid combiners that can sustain high RF power load to interconnect both GSM & UMTS 1900MHz basestations. The arrangement of the couplers feeding the various mall levels were also optimized. DC programming of the couplers was also specified to ensure that the inline BDAs were electrically powered. A radio commissioning plan was finally created to validate expected RSSI and implicit functionality of the system. The site was commissioned in realtime via remote switch access and all performance metrics were monitored.
December 10, 2009 – 4:15 am
Inbuilding RF solutions provide targeted coverage and capacity relief to specific areas which otherwise cannot be covered by the outdoor macro network. I have worked on numerous high-profile inbuilding solutions, one of which is documented below. I was the prime RF designer for this project from start to finish. This project had undergone accelerated build to meet an event deadline and was commissioned within one month of project initiation.
Project requirements were to improve inbuilding coverage for a large stadium before an event held March 2007. The project was initiated on February 2007 and to be constructed in one month. Kick-off meeting was held on site with RF Engineering, represented by myself, along with Civil Engineering, Optimization, Sales, and Client to address the scope of work and possible methods for implementation. Based on discussion from the site visit and RSSI measurements, I performed an extensive RF study of the macro network and analyzed the link budget and pathloss for proper positioning of antennas. I designed the coupling and layout plan. Design margin was also accounted for in case of detection from multiple donors and rising channel utilization of the macro network. I had specified the equipment costs as part of the project budget and had submitted to Planning and management for approval. At this stage, the project was evaluated for its business case.
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November 28, 2009 – 10:38 pm
The objective of this report is to design a parallel 4-bit adder for low power consumption using 0.18 micron technology. The transmission gate implementation of the 4-bit ripple carry adder is chosen. Implementation is based on a bottom-up design methodology from schematic design of individual devices to integration. Critical paths are abstracted and optimized for low power dissipation. The schematic design is translated into prefabrication layout. Simulation of the schematic and layout realizations of the adder is performed and results are discussed. Performance is validated with specifications imposed by the target application.
E&CE437 Project
November 25, 2009 – 6:49 pm
This project utilizes a fuzzy expert system in addressing the inverted pendulum problem since there is inherent uncertainty in the dynamics of the system. Crisp measurements are obtained from the inputs and then fuzzified to see their degree of membership into the fuzzy set. The optimal range for each fuzzy set is then found. After, a set of rules are used to evaluate the resulting force that is applied on the block to counteract the falling pendulum. A process of defuzzification occurs where our applied force is translated into a crisp value. This process is cycled while observing the system behaviour. Some tweaking of fuzzy sets was performed to improve the effectiveness of the system. Matlab was used to simulate the system.
AI Report
November 20, 2009 – 4:50 am
The Singaporean government faces a new challenge to accommodate rising demand for public housing but also strive to retain the nuances from the past. The following architectural study that I wrote shall investigate whether there is a correlation between daily activities held within the premises of a typical apartment complex in relation to morale as found in traditional Kampung ways.
AR1221 Report
November 15, 2009 – 6:51 pm
Flockingducks (http://fducks.com) is a social network which my partner, Yen Pin Hsiao, and I had created. The service keeps track of your contacts (so you don’t have to). With the ever changing nature of our contact list be it phone numbers, emails, and myriad of other networks, the aim of the service is to consolidate all of the bits of information and synchronize your gadgets in the end.
This project was a labour of love. I recall the days when we sat in William’s coffee shop just on the outskirts of campus, penning out our ideas right after we finished our final semester of university. It was a tremendous effort between the both of us in planning and building the website with everything crafted from scratch and which ultimately took about a year (on a part-time basis) from concept to launch. Till this day, the website is still a testament of the slick craftsmanship and of our creativity.
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November 10, 2009 – 5:51 am
