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Technology Stocks : Ericsson overlook? -- Ignore unavailable to you. Want to Upgrade?


To: elmatador who wrote (2691)1/30/1999 1:27:00 PM
From: Peter J Hudson  Read Replies (1) | Respond to of 5390
 
Elmatador,

Maurice will chew this up and spit it back at you when the sun comes up in NZ, but I can't resist pointing out a few problems with your "facts".

>>As the frequency goes higher, you get more bandwidth so you get more
information transported over the radio medium.<<

You are confusing carrier frequency with bandwidth. 5Mhz of bandwidth at 900Mhz or 1800Mhz is still 5Mhz of bandwidth. The amount of information carried in a given amount of bandwidth is determined by the modulation used.

>>Since WLL only make economic sense in a high density users' area,
this areas usually do not have -in Asia- a lot of room to construct
towers. So we decided to erect masts.<<

In high density areas most obstructions to RF are buildings. It takes a much more substantial foundation to build a tall building that it does to support a monopole. If the buildings aren't high, because of poor soil, the towers don't need to be as high. If the buildings are tall they provide excellent locations for antennas.

>>The soil of a region seating on a sedimentary basin is usually softer. It consists of sediments deposited by water running down the mountain slopes.<< Sounds a lot like San Francisco.

Your soil science doesn't hold water either, but suffice it to say any soil that is supporting a high density population will support WLL infrastructure.

Maurice, give him the rant he deserves. Sorry for butting in.

Pete



To: elmatador who wrote (2691)1/31/1999 5:24:00 PM
From: Maurice Winn  Read Replies (3) | Respond to of 5390
 
Now, let's check out your orthogonality.

2GHz does indeed need more base stations than 820 MHz and the capital cost of the network is much higher. The more dense network is needed to provide coverage due to higher absorption of signals by tree and buildings.

But you'll notice in the USA that the economics of PCS [=2GHz] is proceeding very happily. Capacity is the key. While the basestations are more closely packed, they provide access for more subscribers so they end up fully used anyway. As you tried to say, they also have higher data rates available for a given bandwidth. So you get more bang for your buck, if the signal can get through the leaves, rain and walls.

So the simple fact that there are more of them doesn't mean 2GHz is worse than 820 MHz. That is a bit like the chip rate argument which Ericy is trying to put forward - the VW40 chip rate is higher, therefore it's better. False.

Now on to your earthworks. When you have soft dirt, you don't just build a dirty great concrete foundation. You get smart. Buildings are built to 'float' literally, in big concrete 'boats'. Perhaps your civil engineers were a little backward.

Firstly, there aren't many places where you can't build a building. Secondly, where there ARE buildings, you can put basestations, either on the buildings as already pointed out, or if the ground can take buildings, it can take simple little base station towers. Which by their nature have very low wind loading and negligible earthquake problem because the aim is to support a flimsy aerial, not floor slabs, people, trucks and heavy material items. A service station canopy is more problematic than a cellphone tower because it has wind load and earthquake shear to contend with.

Here is a free tip for your cellphone tower construction.

Get a big post hole borer like they have to dig round holes for building piles, of which you will find many in the yellow pages. Dig down deep enough so that the cellphone tower 'floats' in the hole. Your engineers can calculate how heavy the tower will be and therefore how deep they need to dig. To be really smart alecky, they could put a bit of cathodic protection on the tower to protect the [presumably steel] part sticking into the wet ground.

If it's a windy location, they'll need to go deep enough to provide lateral stability too against wind.

I call it PoleHole [TM]. I charge 10% for each one used.

They are really quick to build [24 hours ready to transmit]. You can disguise the pole as a palm tree [which is done in NZ] and the neighbours will think somebody has put a nice new tree in, so no more complaints about visual pollution.

People will even demand one on their property to enhance property value [guaranteed good reception a bonus].

You worried about tree roots [not usually a problem in a built up area where WLL will go]. No problem - you just dig right through them with the drill.

We had Rajala going on for a while about how WLL is no good. Nevertheless, you get more capacity with WLL instead of mobile and therefore lower costs, which are important for most people. WLL costs have dropped along with cdmaOne costs. Qualcomm is selling WLL systems. It might be that your experience with a certain type of WLL led you to think that therefore all WLL is bad.

On to GSM. Will it hit the wall? It already has. NOBODY is touting it as a 3G option. Not even L M Ericsson who you can be sure would have done if they thought they could. They want to use Qualcomm's technology, though they deny they need it, thought they say Qualcomm is holding up 3G? Talk about irrational!!!

Lastly on sediment. Anywhere you don't have rock is sediment. Some of it is soft peat goo. Mostly it is firm enough to build stuff on. Each individual site needs consideration. Asia is not one big peat bog. Neither is Britain though one could be forgiven for thinking it is.

Also, cdma2000 is so smart, that they can use PoleHole[TM] and use water as a balancing device - the verticality of the pole is constantly monitored and water shifted from side to side to balance the pole. The altitude can also be varied by increasing or reducing the water in the pole, thereby raising the pole as trees grow to maintain an uninterrupted signal. The water is pumped to or removed from groundwater.

Life is simple! You just have to know how.

Maurice
[Once upon a time I really was a civil engineer. Still civil, not so much engineer]



To: elmatador who wrote (2691)2/1/1999 1:16:00 AM
From: Clarksterh  Respond to of 5390
 
ElMatador - Since WLL only make economic sense in a high density users' area

Actually all of the economic studies I've seen indicate that high density (e.g. Manhattan, downtown Mexico City, ...) areas are precisely where wireline is still cheaper. It is in low density to medium density (suburbs and rural) that WLL has an advantage over wireline since in wireline you pay by the foot, but in WLL you have high baseline costs, but each additional user costs little.

Clark

PS You are of course right that trees et all are an issue, but don't take DECT as a good example of the possible range of a 2 GHz WLL system. DECT was designed largely for internal to buildings use and so it has timing limitations and other things which limit its range. GSM, US-TDMA, and CDMAOne don't have the same problems.