Moble Phone signal (part 2) Help please

Its very hard to know exactly what is going on with those figures without knowing how and where they where taken and exactly what they represent.

I Assume that they are field strength in dBm as displayed on some sort of app in the phone.

What the variation represents is anybodies guess.
But what is certain is that the best case is 7dB of gain on the RFI aerial ..... a gain but not a massive margin but at worst it only gains 1dB ..... not even statisicly relivent.
The laser seems to provide 9dB of gain in one line but as little as zero dB on another.
So that means on both aerials .. between a modest gain and pretty much no gain at all

The problem with most modern phones is that either they don't have any direct Aerial connection and require some sort of proximity coupling, Or If they do have an aerial socket it performs poorly.

I and others like me who have some sort of RF trade background have tried to achieve in car or in home range performance with mobile phones and some sort of external aerial and found improvements over a bare phone in hand illusive.

THE single biggest issue is getting sucessful coupling to the phone.
Note that neither Apple nor Samsung seem to offer a genuine car kit.

I do not believe it is a problem with the aerials, Because I do a little work with other things that operate on the mobile networks.
Systems that we formally commission and require field strength readings.
Those systems all have external aerials and properly constituted aerial connectors.

It seems to me that the deigners of hand held phones have no interest in them being used with external aerials ..... thus this whole car kit exercise seems to be a fools errand.
In that there is more loss in the connection between the phone and the kit than a perfectly functional high gain aerial can provide.

For those who are serious about long range in car mobile phone reception there are still fixed in car mobile phones available ...... units that have properly constituted aerial connections ...... pick up any trucking magazine and you will find the adds.

I do not believe that changing the aerial will give you any better results.

sorry

cheers

As said, unless the phone is connected to the aerial, any gain is miniscule.

The inductive cradles are really just a nice looking charging station.

lyndon,
As per what Gronk says above, inductive cradles are basically useless. Even more so now that 4G is here.

That hand written note does indicate an improvement of about 2 - 3 dbm in the city. That is a seriously marginal improvement, You may pick up a signal 30 seconds quicker when driving. Simply moving your iphone 12" may do the same thing though. It also begs the question, what carrier and frequency were those measurements made on? There is a better than even chance that the frequency is different to that in the bush.

Another thing to note is the frequency bandwidth of the cradle and the Antenna.
Taking Telstra as an example, they use 850Mhz and some 1800 in some cities for 3G, 2100mhz in some cities, 2600Mhz in other cities and areas, and now will focus on 700mhz outside the cities for 4G. A phone call can even share all 4G frequencies now to get better coverage.

I doubt that your cradle / antenna can work with all of those frequencies, in fact if the antenna and cradle is not specified for all those, it will REDUCE the signal at times. Note some new antennas do claim to work across 700 to 2600 Mhz bands, this may be the case, but connected through an inductive coupler they are unlikely to perform well across all frequencies, especially since a single frequency antenna don't even work with an inductive coupler with any noticeable gain.

In the old days an 850Mhz Next G antenna would work ( with an external antenna socket on a phone) but the days of having a single band external antenna are long gone.

I would discourage anyone from trying to get better reception in a vehicle with inductive cradles and external antennas, the results are totally disappointing.AT BEST.

One last point is that no UHF antenna will work reliably on a bullbar anyway. It should be in the roof of the vehicle if long range is the goal. Especially for the higher frequencies.

The odds are firmly stacked against any significant signal improvement I'm afraid.

Hi Folks
A big thank you for all of your informative replies. Sadly, it was sort of what I expected :-(
I wished I had been advised of this before purchasing the kit.
As mentioned the antenna will be going to a lower location also. Readings were done with the RF also on the roof to give a direct comparison. The RF is a much bigger antenna when side by side with the other. But as said, results are very marginal at best.
As said, it's not something we use often but is nice to have when we travel.
Would anyone care to post a link to one of the "trucking" phones mentioned? Can't say I'm going to rush out and buy one with no immediate need but may do so when we travel extensively in the future (read long time in the future, LOL)
What to do...............................?

I do not believe there is any problem at all getting multiband aerials to work.
The UHF and low microwave frequencies that are used can be made to work together.

The aerials from any reputable supplier will be tested, specified and guaranteed to work as claimed.

Yeh I have had a few multi-band aerials apart .... I undersrtand enough about aerial design to see what has been done and to identify the elements.

THE problem is coupling to the phone.

With 4G a current reality, some of the aerial systems in the phones and the crazy stuff they do to make things work, external aerials will continue to be pretty much a non event on hand held mobiles.

The current 4G technology and that following it uses a complex multi aerial multi path system called MIMO.
The aerial in the phone or access point most likely is not a simple single antenna ...... it in the better units will be a multi aerial array ..... no single aerial can possibly perform as well.

Most of the standalone 4G wireless access points, both pocket units and full blown commercial units have 2 aerial sockets ..... to achieve best results either two seperate aerials have to be fitted or a MIMO aray which has two cables and two plugs.

Yeh things are not as simple as they once where.

cheers

Hello Lyndon,
While not directly answering your question I have an external antenna for my phone which is a Telstra "ZTE" smart phone, only cheap but it does have a port on the back for a external antenna.
I use the antenna with a patch lead which connects the antenna lead with the phone port.
I use this system whenever I go outback because my Samsung with TPG is useless when I cross the Blue Mountains from Sydney.
The family have both numbers and know to call the "outback" phone when we are traveling.
it is on a prepaid long life deal so doesn't cost alot to have sitting there when not traveling.
William

A google search found, "truckphone.com.au" there not smart phones though.

It is worth mentioning here that at the moment VOICE IS ALMOST NEVER TRANSMITTED ON 4G ONLY DATA.
With the exception of a very few phones capable of VoLTE.
So if you bought a new phone thinking 4G will be better it may not if you just use the phone for voice calls

Quote
Voice calls are still made over 3G networks, for now. Even in the cities where 4G is available, all voice calls are connected on the older 3G networks. Trials are taking place to upgrade the 4G networks to have voice capabilities, but this could take several years to implement.

4G networks are still slowly rolling out to regional areas, meaning that 3G still provides the backbone coverage in many less populous areas across the country.

Some more up to date links

http://www.cnet.com/au/news/vodafone-cracks-the-volte-bringing-voice-calls-over-4g/

https://www.telstra.com.au/coverage-networks/volte

Over the next three years we will build 429 new 3G/4G towers to deliver mobile service to over 400 communities who currently have no coverage in or around their towns.
In addition to the new mobile towers, we will be installing 250 Small Cells to deliver high speed 4G data services in some small country towns where suitable Telstra infrastructure is available.
At this stage, the Small Cell technology can only provide data services, however, we are working on implementing Voice over LTE technology which will allow customers to make voice calls using 4G
.
https://www.whistleout.com.au/MobilePhones/Guides/The-difference-between-3G-and-4G

http://www.optus.com.au/shop/mobile/network/4g


Most up to date article
https://www.finder.com.au/mobile-phones/4g-lte

Also at the moment and going forward VoLTE is not available on PREPAID There are no plans to remove 3G in the near future as the great majority of mobiles are 3G and there would be a scream of they all became useless over night

I have just bought a Galaxy S6 but in my area that has 4G the voice calls still go on 3G event though an S6 is VoLTE capable as its on Prepaid

Type or copy the below numerical number into your phone keypad on the call section, it should give you accurate strength data, its called 'field test mode'.
*3001#12345#*

I just had a look at it , it seems a bit more complicated than i last remember, maybe google will have more details.

Lyndon, your options are: 1. Status quo 2. Illegal amplifier with cradle- lifts gain by 30 to 40 dB 3. Use your sim in second hand satphone (about $500) but no data.

Having said that we had 3G coverage on hand held iPhones in some extremely remote areas on recent trip: 60 km north of Papunya and 50 km north of Surveyor Generals Corner.