Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!usc!zaphod.mps.ohio-state.edu!casbah.acns.nwu.edu!accuvax.nwu.edu!nucsrl!telecom-request From: dave@westmark.westmark.com (Dave Levenson) Newsgroups: comp.dcom.telecom Subject: Re: CMT Ant-Rooftop vs Rubber Duckie Message-ID: <16087@accuvax.nwu.edu> Date: 15 Jan 91 13:05:45 GMT Sender: news@accuvax.nwu.edu Organization: Westmark, Inc., Warren, NJ, USA Lines: 34 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 11, Issue 40, Message 9 of 11 In article <16050@accuvax.nwu.edu>, mearle@pro-party.cts.com (Mark Earle) writes: > Well-in PRACTICAL terms, the phone on it's rubber duckie works as well > as when on a "real" antenna. Typical: On I-37, I lose the "home" > carrier at mile marker 90 with the "real" and with the rubber duckie > it's at mile marker 88. Big deal! Similar observations at other > "boundaries". Note, this is not ONE cell -- I'm not in that contest > ... but only the point I lose "home" and have to use "roam" > facilities. I think Mark is saying that he gets switched from HOME to ROAM at approximately the same point regardless of which antenna he's using. Somehow, that is not surprising. One switches from HOME to ROAM when one's cellular telephone set discovers that it is closer to a cell belonging to a system other than the one it considers to be its home system. That should happen at the same geographic location every time, unless cells are being created or moved. The fact that it varies by a mile or two is probably the result of some granularity introduced by the timing of the periodic locate interval in the mobile unit. I think they typically re-scan the setup channels and re-determine which one is strongest every minute or two when they're idle. The mobile antenna choice probably affects overall signal strength, and possibly the directionality of the coverage, but not the relative strength of two neighboring carriers. Dave Levenson Internet: dave@westmark.com Westmark, Inc. UUCP: {uunet | rutgers | att}!westmark!dave Warren, NJ, USA AT&T Mail: !westmark!dave Voice: 908 647 0900 Fax: 908 647 6857