Please download to get full document.

View again

of 2
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.


Document Related
Document Description
The Radio Frequency Engineers challenges
Document Share
Document Tags
Document Transcript
  The RF Engineer  James L Bradley July - 2007One scenario that I often encounter in the world of wireless is our propensityto lay everything at the feet of the software, and in a great majority of the caseswe have shifted away from the basics of RF design and planning. RF retains asimilar attitude as to a small child, ‘ you never know where it is going and inwhat shape or form it will be when it arrives’ . Some of the basic theoryhangs around in small corners of the engineering lab, supported by the peoplewho climb the hills, drive through the cities looking for dead-spots andassembling data, and then composing a presentation to the management whoonly understand that they have just spent millions on a software package thatwill not only solve all the mysteries of communication, but on why the climate ischanging.While the tried and true RF Engineer’s stand there with mouths agapelistening to the tirade bouncing off their ears, in most cases not getting a word inedgeways, from management on why their multimillion dollar system won’t work,albeit a solution is usually found. It is a typical scenario, not in all cases – butconsider this, where in this age of mass communications, with imported videofrom around the world, fiber laid so thick across the globe that a meteor strikewould barely shake a light-bulb hanging on a bare wire from the ceiling, themanagement only knows someone is telling them it won’t work. Millions of bytesper sec fly around the world containing information that defies the imagination,now you stand there as an RF Engineer telling the board of directors that theirbuddies driving around in their $450,000 Bentley’s will not be able tocommunicate in all parts of his fine city – not well received. The RF Engineer today faces more than just the physics of radio wavepropagation, where they bang their heads against the wall in fighting the RFenvironmentalists who state with unequivocal certainty that RF is raising theincidence of asthma, autistic children and in some cases increasing mad cowdisease – in addition, you can’t put that antenna in their backyard. Getting apermit today, in areas where most of the traffic will be generated is not unlikeattempting to walk on water. The RF EngineerPage 1    And these actions take place after the engineer(s) have completed monthsand months of survey’s and spent countless dollars in their search, that includesoff the air signal analysis, along with burning the midnight oil writing countlessreports on why or why not a certain location will or will not serve the goal. As abreed they all are jealous in their demand for height, more height and extremeheight – hoping to achieve multiple line-of-sight paths, some mistake this as agoal in making their task an easy one – no, it is just a basic premise in high-frequency design. After the AM band, the RF Engineer climbs onto the “height isgood” bandwagon, until he runs smack into the FCC and their frequencyallocations, new and grandfathered, and he has to sit back and reassess hisdesign or incorporate changes he guards with a passion. They lay the topo’s end –to- end across the engineering lab, spend hourslooking at lines on these maps, spilling countless cups of coffee on them, smilewhen they find a couple of hills that will enhance their plan. They sleep, eat andwalk the RF world – dreaming of their signal entering and visiting every place onthe earth and beyond. They talk mostly in a language that even seasonedsoftware developers do not understand, as some RF old timers have a difficulttime comprehending code other than the one Sam and Alfred developed in the1830s.Why not? They’re RF Engineers.Over the years, they, more than most, understand that radio systems demandtradeoffs or compromises, where coverage, quality and capacity must bebalanced in achieving their desired level of performance.Wider coverage, normally a good thing, means using higher-powered mobileswhich results in more interference, a loss of quality.Increased capacity demands more calls in the same amount of spectrum,which results in dropped or blocked calls in the same spectrum and again a lossof quality.Although dated, the saying, radio system are not sold, but engineered, isnever truer than in today’s environment of increased demand and limited access. The RF EngineerPage 2  
Search Related
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks