Selected Daily Notes Archive (Home Page has current notes)
Oldest (Page 1) to most new (Page 52)
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22) (23) (24) (25) (26) (27) (28) (29) (30) (31) (32) (33) (34) (35) (36) (37) (38) (39) (40) (41) (42) (43)(44) (45)(46) (47) (48) (49) (50) (51) (52)
October 16, 2002
In radio a digital signal always means a less robust signal than analog. Digital doesn't go as far, requiring many more multi-million dollar base stations to cover the same area as analog. It is cost efficient for a cellular carrier to switch to digital, since they can carry several calls on a single frequency, instead of just one for analog. But coverage and audio quality will suffer. H reports below from South Dakota:
Dear Tom,
You've discussed AMPS coverage in rural locations (internal link). Despite this being 2002, there's still very little in the way of digital coverage here in South Dakota. Cellular One (Western Wireless) has the only digital coverage, and their footprint is expanding at a rather impressive rate. They initially deployed TDMA, but have begun migrating sites to CDMA. Word, according to the trade magazines, is they are eying a transition to GSM.
In the interest of complete disclosure, Sioux Falls, the largest city with 125,000, has decent cellular coverage with a new Nextel installation, Sprint, Verizon, RCC Unicel (small GSM only carrier similar in marketing paradigm to Cricket) and perhaps T- Mobile, in addition to the Western Wireless digital coverage. Rapid City, number two in population with about 55,000 has a tiny Qwest digital footprint, Verizon, and WW. With Qwest being run into the ground by stupid execs; I'm waiting to see who that asset will be sold to. Verizon has put most of their effort into the cities where there is a student population -- Brookings with SD State, Vermillion with the U of SD, and Madison with Dakota State. Population densities are, as one might guess, significantly higher in the college towns.
For the bulk of the state, however, (in terms of area, not population), the coverage is AMPS, and not even very advanced AMPS.
The cellular sites were built in the early 90s by CommNet cellular, and are spaced from 20 to 40 miles distant. I travel regularly on US 14. With a handheld operating at the full .6w, calls were never able to be handed off as the call faded before reaching the edge of the cell. It wasn't until I purchased a rather nice external antenna that I was able to have a conversation spanning cells. Needless to say, this simple, aged feature of cellular communications was quite impressive to me. It never worked before.
For work, we use the old Motorola bag phones with the 3w transmitter and external antenna. They're harder and harder to find, and the models we have are at least 8 years old. They work, and where we travel in the state, coverage is still amazingly pathetic. I've been in areas in South Dakota where there was zero coverage, even with the bag phones and antennas. Nobody who travels anywhere out of the populated areas is impressed by digital or handheld phones. I suspect that this is one of the few states where people still clamor over a hulking black bag phone, and look with disdain at the shrinking size of cell phones. We did pick up what is probably one of the last and most feature laden bag phones about two years ago, new. It had a most amazing feature. Something which greatly impressed us: Caller ID.
Your prediction of a phase-out of AMPS in five years is a bit optimistic, I think. The phase out will happen when the present equipment breaks, and AMPS-compatible replacements can't be found. Only then will things go digital here. I do see it isn't easy to build a cellular network to cover counties with a population density of less than 3 people per square mile. Want more specifics?
I've endlessly nagged Verizon, my cellular provider, to transition the larger cities (Pierre, where I live has 13,000) to digital but they're not too interested in doing that it seems. AT&T has nothing here, T-Mobile, Cingular, nothing. In some succinct emails with a Verizon RF Engineer out of Minneapolis, he was rather forthcoming with an explanation. The gist of his comment was that the Verizon execs (much like most cellular execs) live in Sub/Urban markets, and have zero understanding of what terrain, demographics, and the reality of rural and frontier markets. Hence, they're not too interested in the sparse areas. I inquired as to the expansion of digital coverage, and the target was, as you might guess, on well-traveled corridors, and not much beyond that.
Western Wireless has astounded me as to their endless expansion of digital coverage. Granted, they're really hurting financially, but they got significant Federal grants to provide wireless coverage in areas like Pine Ridge -- a place which didn't even have landline service. That blows my mind. How they could be so overlooked as to have been ignored by Qwest.
I see the F.C.C. announcement not so much a phase-out of AMPS, but merely the elimination of the requirement to provide AMPS service. There may not be a future increase in AMPS coverage, but the status quo will be the same long into the future.
H.
October 14, 2002
Okay, I know I haven't been updating this page as often as I should, but I am still answering all of my e-mail and I am still updating pages. It's just that there are 332 pages now at telecomwriting.com and I do have other things in my life to take care of. Good news for you: it's getting a little colder here in California's Central valley and so in the upcoming months I will be indoors more and thus writing more. I look forward to hearing from you.
October 7, 2002
Has 3G (internal link) stalled? It seems so, as the article below indicates. But perhaps this is for the best, the infrastructure for it isn't in place. Promising 3G would only disappoint customers, people who are still waiting for expensive 2.5G services like GPRS or EDGE to appear, improve, and drop in price. Since we are still waiting for 2.5G, it will probably take many years for 3G to come along:
.AT&T Wireless Sees No Demand for WCDMA Service Thu Oct 3, 2:05 PM ET
PARIS (Reuters) - AT&T Wireless Services Inc. , the No. 3 U.S. wireless telephone company, on Thursday said it was seeing no demand for the long anticipated high-speed wireless service based on the WCDMA format.
"We don't see anything in the market driving demand for Wideband CDMA," said Leo Nikkari, AT&T Wireless' director of 3G industry relations. "I don't see anything pushing us to an early WCDMA launch," he said at the UMTS and Mobile Internet conference in Paris.
WCDMA, or Wideband Code Division Multiple Access, promises data speeds of about 2 megabits per second, which is more than 13 times faster than AT&T Wireless's current high-speed network that allows customers to easily check e-mail, surf the Web, and download applications. . . .
October 2, 2002
It's been determined once again that cellular telephones do not cause cancer. Here's a snippet from the A.P. report covering the latest trial. Download the court's decision to read it yourself. (internal link -- .pdf file) And read some common sense on this subject by clicking here (internal link).
Ruling Threatens Cell Phone Suits
GRETCHEN PARKER Associated Press Writer (All rights reserved)
"BALTIMORE (AP) - The ruling by a federal judge that tossed out an $800 million lawsuit against Motorola could hinder other suits filed by cell-phone users who claim their phones gave them brain cancer, attorneys said.
"Clearly from the outset, it's not going to bode well for those cases," said attorney John Angelos, who filed the lawsuit against Motorola on behalf of Christopher Newman.
U.S. District Judge Catherine Blake ruled Monday that none of the evidence submitted by Newman was substantial enough to warrant a trial. Blake considered the evidence and experts' testimony presented during a five-day hearing in February.
The telecommunications world watched the case closely. If it went to trial, it would have opened the door to other suits against the $45 billion industry. Other similar claims against mobile-phone carriers also have failed. . . "
September 30, 2002
Improved Mobile Telephone Service (internal link) may be gone from the public switched telephone network but the system may still be working in private use. Are they any scanner buffs in the midwest who could tell us more? A reader reports:
Hi Tom,
Somewhere in Northwest Illinois, or possibly SE Iowa, an IMTS system is still operating. I have heard it. I haven't had enough time to find which city, although I have a few suspects. I think it is only used by the local telephone company for their own use.
IMTS is the only system that I've run into that marks the next/signalling channel with a 2000 cycle tone. That's what I heard. I did jump to the IMTS conclusion on my own, but it sure seems plausible.
I have run into a scanner buff closer to that area, he has said he was able to hear it and will check it out when he's travelling in near there. He knows IMTS, said he built a circuit to squelch his receiver when the 2000 was on.
I'll let you know if I find anything else.
Okay, you may think nothing is happening here but it is. I'm trying to re-write various sections on different pages about modulation and carrier. Tough, slow going. Will write and post soon.
I have a mess of notes on modulation from three experts. I am trying to reconcile their comments so I can put them together on a page that makes sense. Some of their remarks challenge what I and many others have written on modulation. That means I may have to re-write small portions of perhaps a dozen pages, ranging from my modulation page (duh!) to pages on landline and mobile telephone history. This is a tough project.
This morning I attend the formal dedication and opening of the new Plant and Environmental Sciences Building at the University of California at Davis. Yes, the same campus that MTV films for "Sorority Life." Some of the environmental horticulture professors I know have shiny new laboratories and I wish to congratulate them. Perhaps my old boss will be there, John Gray, whom I haven't seen in at least 10 years. Then back to web work.
I see this cat in many places. Thanks to the web site below I now know what it means:
"The maneki neko or beckoning cat is seen all over Japan, where its message, as on this web site, is 'Please come in. You're welcome.' Japanese body language differs from that of the West in some respects. In particular, the gesture meaning 'Come here' is done the other way up, i.e. with the palm downward. The legend states that a poor temple owner could no longer afford to keep a cat. He apologized to the cat and set him free. One day, a wealthy lord was walking by the temple when he saw the cat beckoning to him. The lord was interested, and as he walked toward the cat, lightning hit a tree and it fell to the road where he was previously standing. Grateful to the cat who saved his life, the lord funded the temple. People came to see the temple from all over Japan, and the owner made clay statues of his cat with the left paw raised in a beckoning gesture. The 'maneki neko' temple is Goutokuji."
X-rays are good for you? Or at least not harmful? How is that possible? Check out this fascinating article that Mark van der Hoek forwarded to me:
I think this is quite the same with RF exposure. I tell people, if RF is such a hazard, why aren't the workers in that industry, civilian and military, people exposed to far higher rates than cell phone users, show higher rates of cancer than the general public? Wouldn't the Communications Workers of America raise an alarm? And what about the electrical industry? Ever heard their unions making a fuss about too much E.M.F.? No. But if there was a higher rate than the general populace, you know that those unions, and their lawyers, would let us know.
I've often heard, "The keypad on my mobile is too small to do anything! How will anyone make it a useful product without a full size keyboard?" Well, that indeed is a challenging problem. Here's a fascinating solution, a virtual keyboard, projected by a laser so that you can type on almost any flat surface. Now all we need is a virtual screen, a laser projecter that would simulate. possibly with a hologram, a 17" monitor. Wouldn't that be cool?
From the BBC: http://www.bbc.co.uk/science/tw/2002/may08keyboard.shtml (external link) Link now dead, thanks, BBC!
"Introducing a keyboard that literally lets you type on your desktop. It uses a small diode laser and some special optics to project a keyboard onto any surface that's reasonably flat. In the same box is a special infrared system that detects the movements of the user's fingers across the projected keyboard and links it back to the computer. It can be linked to conventional PCs or hand-held computers and the manufacturers plan to connect it to mobile phones. They say that the virtual keyboard would be particularly useful in hospitals and other environments where conventional keyboards could collect dust. . . . (continues at the BBC link above)
The image above comes from Japan, with Doraemon and the gang celebrating mid-autumn festival. Click on this link to get a special Autumn greeting. Note how the stars circle around your cursor each time you move it. http://www.doraemon-land.com/doraemon/doraut2000.htm (external link) And click on this link to learn all about Doraemon. http://www.doraemon-land.com/ (external link) Links now dead.
