EEVblog Electronics Community Forum
Electronics => RF, Microwave, Ham Radio => Topic started by: Houseman on November 06, 2020, 10:51:18 am
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Hi forum.
I really need your help in order to understand if it is safe or not.
Inside my house I have very poor 2G/3G/4G cellular signal.
Calls are only possible in a specific point of the house outside the window where I get at fairly decent signal.
So I have bought a Chinese quad-band BOOSTER that consists of an external antenna / an 2G-G-4G amplifier and / a internal stylus antenna.
I have placed the external antenna at that point and now inside I can make calls.
Now I am concerning about safety especially since I have a young child playing around.
Item does not have a CE certification.
So I have measured with a spectrum analyzer a 3-meter distance and get the graph showed in the files.
The signal is at least 34dBm above the noise floor with a peak of -42dBm.
It can be shown the two frequency bands occupied.
How information can I extract from this graph?
I do not want to have a harmful device inside my house.
Can you suggest me some other test to perform in order to understand better?
Thank You so much.
Best regards
Steve
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The maximum exposure levels are usually given in V/m (electric field strength). To get this value you need the voltage and the antenna factor.
https://www.keysight.com/main/editorial.jspx?cc=DE&lc=ger&ckey=1000001962:epsg:faq&nid=-33762.752176&id=1000001962:epsg:faq (https://www.keysight.com/main/editorial.jspx?cc=DE&lc=ger&ckey=1000001962:epsg:faq&nid=-33762.752176&id=1000001962:epsg:faq)
You can take a look at the exposure limits given by the ICNIRP. But most countries define a lower limit for endless exposure times. Usually ca. 90 V/m at GSM900.
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Signal level depends on antenna which you're using, so you're needs to perform the same measurement with the same antenna for known signal level in order to get absolute value.
In other words, you're needs calibration with reference source.
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It would be interesting to do the same measurement for your phone to see how it compares.
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-30 dBm is 1 micro watt.
-34 dBm is less than half a microwatt.
a mobilephone is somwhere in the range of 200 mili watt or about 23dBm.
Your phone is radiating somewhere close to 400 times more and is considerable more than your phone repeater.
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geggi1, we don't know physical size and efficiency of antenna and test setup which was used for measurement, so we cannot make assumptions if power flux density level is within safe range. It can exceed safe level or not. We don't know. Because we don't know what absolute level corresponds to 0 dB on his measurement
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Well if its true and you are from Italy you should know that is illegal to use such think.
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Measured and by antenna picked up power, here -30 dBm, can be assumed that it is in same range as amount of power that can be picked up by a human body at similar distance.
It is dangerous as it is EM waves transferring energy which is creating heat when these waves are absorbed in skin and fat close to surface of human body.
It is easy measured with a simple thermometer how much skin-temperature is increased.
Human body have inbuilt functions trying to handle local heating. Typical methods is by increasing blood flow to spread heat more even over a bigger area and then emit that heat with aid of sweat transpiration.
More intense heat and body reacts with reflexes trying to avoid touching a very warm surface, such as a hot soldering iron.
Measured amount of power is less then -30 dBm. It corresponds to 0.000001 Watt
Assume a human body can absorb ten times more power then your antenna, it is ten times more effective as antenna, and resulting absorbed power is 0.00001W.
We can compare this to other sources of same kind of EM waves.
A 1W flashlight pointing against directly at your body makes your body receive 100.000 times more radiation and it will induce much higher levels of heat locally at your body. Depth of radiation under your skin is similar as for 900 MHz EM waves, 99,9% of all radiation is absorbed within 10mm below skin, but heat will continue to spread deeper even after flashlight is turned of.
The biggest and strongest local EM source we know about is hanging outside, our sun. At a clear day will sun emits peak 2000W/m² at earth surface. As an adult human body expose about 1 m² of surface against sun if not using protecting clothes can we absorb up to half of that 2000W and the other half is reflected if it is a pale skin. Absorbed amount of power is then then about 1000W. Really a lot of heat to handle. Body internal cooling system have to run as hard as possible to avoid permanent harm and adding as much coolant liquid as possible is often important a sunny and warm day.
As with all kinds of radiation is time a critical factor when comparing resulting radiation wounds.
Say that a terrible accident happen and you get exposed by sun for 1 minute totally unprotected. Amount of absorbed energy in your body is then equal to amount of energy absorbed 3m away from your repeater during a period of 1900 years.
Turn it the other way, avoid sun for one minute and you have compensated for your router RF radiation for 1900 years.
As radiation levels decay with square of distance, keep at least 50 meter distance from heating elements inside house.
A kitchen stove can easily emit a 2000-3000 Watts and the closer you are, the bigger risk for burning wounds.
Burning risk is here a factor exactly same as for a flashlight or a cellphone which can emit up to +30 dBm (1W), about 1 million times stronger then your measured -30 dBm from repeater.
If measuring a active cellphone from 3m distance will probably show similar result as for the router.
Difference is that cellphone is often held at a much shorter distance then 3m.
Be also aware of risk due to EM waves radiated from light bulbs indoor. They emits often more then 10W, not seldom close to your eyes.
Even worse, a computer screen is sending waves directly against your face and eyes, not seldom with 50W or even a bit more, including IR waves.
EM waves are causing heat effects but with increasing frequency increase level of sporadic harm at atomic level. A such harm is when a subatomic particle is kicked away from its atom, a first step to cause permanent cell modification. That danger increase with frequency. For frequencies corresponding to visible light-waves is it almost never possible to kick atomic particles away from its atom as needed energy level is too high.
For next known frequency range upward, UV-waves is it more possible and at even higher frequencies, x-ray, is it potential even more harmful as almost all radiation now is in shape of particle radiation and no EM waves.
It is same type of X-ray that is radiating at us in higher amount when traveling with airplane or when examine teethes at dentist.
For real low frequencies, almost DC, such as 900MHz which is at least a million times lower frequency then UV is it really not even possible to kick away an electron from its atom as needed energy level to do so not is even theoretical is possible.
Even lower frequencies with high radiation levels found in in many houses is in frequency range 50 or 60 Hz and is emitted in real high amount as magnetic radiation. Human body is way to short antenna to become an absorbent of energy at these wavelengths. Only possible way to absorb energy at these frequencies is by direct connection between electrical wires and body.
Even at real small distance between an electrical wire and skin, and transferred energy is much reduced.
From above examples, it is a clear relation between EM wave frequencies and human body efficiency as a wireless receiver.
Question "is GSM booster radiation levels safe for health" can with above text now be better put in perspective.
The booster consumes probably 10W but emits max 1W at relative safe frequency, 900MHz. It is the remaining 9W that are more dangerous as they not just goes up in smoke, but are emitted as heat-loss within IR-range, which is much more dangerous due to its higher frequency compared to 900 MHz. IR is slightly less harmful then light bulbs that radiates mainly at higher frequencies but as it is around 400 THz is it 400 times higher frequency then 900MHz.
If radiation levels corresponding to a 10W light bulb or more not exist inside your house, and if all window are blocked from sunlight entering inside house and emits its radiation, yes heat loss from your repeater, all 10W of it, are a risk for your health as it now a dominating radiation source in your house, as long as it not is any human bodies inside house as such emits a lot more radiation.
If absolute no radiation sources exist inside your house, it is a disadvantage as temperature then not can go above absolute zero, -273C.
To keep temperature in balance must human body and its surrounding constant absorb about same amount of radiation as it emits.
A human body will die within a minute without any external radiation.
Your body is a radiation source, emits 100W or more of heat that may be absorbed by other human bodies. Emitted in IR range. Your body is also a dangerous wave-converter, as it converts absorbed less harmful 900MHz radiation to IR-radiation that then can be re-emitted to surrounding environment.
Avoid radiation emitted from other humans and avoid sun-radiation, both are scientifically proved dangerous for your health.
Health problem due to GSM-repeater is harder to measure as its radiation level often is so much weaker then more possible harmful radiation sources in same room, such as a light bulb or a heating element, which is assumed to be relative safe.
Why fear 1000W at 900MHz, causing about same amount of heat radiation as a conventional electrical heating element at that amount of power?
Government regulation related healthy or unsafe radiation level are all based on guessed fear level, as it not exist any scientific prof in any direction for any disease or harm, except for known facts that EM-waves absorbs as heat and nothing else.
Our strongest source of all sorts radiation, the sun, is however less regulated.
Radiation-levels levels from sun is known that we can survive for at least shorter periods, which is our practical health level.
Even hotter or sunshine for too long period is uncomfortable,. Can cause dangerous dehydration and skin burn.
With low amount protecting ozone can UV-radiation from sun faster reach dangerous levels at which permanent cell-wounds can occur. Most of these wound are repaired automatically. If not, can it result in dangerous health problem.
Eyes is a special problem. Eyes can be burnt by sun at an even shorter time then skin as an eye can focus radiation to a smaller spot, causing short period with high intensity of radiation in bottom of eye. That kind of wound can not allways be repaired by body itself or by doctors..
That problem does not exist at 900MHz as wavelength is too low to be focus-able with an optical lens.
Government regulation regarding allowed RF-levels and frequencies, to avoid interfere other equipment or blocking frequencies used for important communication should be respected.
On the other hand, if living in a very rural place where radio/telephone/TV-signals are weak due to long distance or blocking terrain and no neighbors, will signals you equipment generate be equally blocked in other direction by same terrain.
Airplane communication can still be interfered even from a rural place, but it is a seldom reported problem.
Known such interference with airplane communication have been mostly close to airport, near or at ground.
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Well if its true and you are from Italy you should know that is illegal to use such think.
What is illegal?
Using a phone booster to power up signal strength?
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Using a phone booster to power up signal strength?
Yes!
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Using a phone booster to power up signal strength?
Yes!
Uh, didn't never know actually.Sorry Why?
It's a CE certification question or something else?
Please tell me.
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;) Simple only the Cellphone Operator are permit to Transmit on the Band the "Rent" from the Goverment for a LOT of Money.
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The booster is likely no more powerful at distance than a regular wi-fi access point. Don't worry about it. Your phone may actually reduce its power as well, thinking it is closer to the cell tower than it really is.
I'm not sure about Italty, but for example in the US boosters are "basically" allowed, but must have at least some sort review by the cellular carriers as "ok" to use with their system. They want to limit power, insure quality of signal, etc., as to avoid interference with the rest of the system. There is probably some FCC regulation too (our govering body for RF) likely the Part 15 low power allowance. That being said I'm sure there are lots of crappy imports in use. This is why carriers frown upon them.
We have two types of cellular helping devices, boosters and pico/femto/"small sized" nodes. The boosters do just that, they attempt boost/repeat/amplify the existing recieved over air signals at a location and are often used in rural areas with a directional antenna pointed at town. Results are mixed as they're not terribly intelligent devices, just amplifying what they hear and hoping for the best. The other type are basically little full duplex cell sites in a box with a connection to your home internet for backhaul. These are sold by the individual carriers for use on their specific network only and are generally preferred--provided you have internet!
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If I were you I would put send back the GSM booster unless somebody at your cell network tells you its okay.
Instead, set up a passive system with a directional (I would use a log periodic antenna) connected to an indoor omni antenna, connected with a length of LMR-400 or similar low loss 50 ohm coax cable. KIeep the coax as short as you can.
As it does not transmit this is safe and legal. Point the directional antenna at your nearest, strongest cell site.
This will act like a bidirectional tunnel for the signals. It doesn't have to be strong, just give them a way around the obstacle in both directions.
I would not use non-type accepted devices, you might get in trouble. If that doesn't work, ask your cellular network provider if they rent or lend out a cell extender device of the appropriate, legal kind, or have any other ideas. They will appreciate your coming to them and asking.
I hope that I am making it clear that all this is is two antennas with some coax between them.
Another way to extend signals is using a reflector of some kind to reflect the signals like a mirror, both ways, but like a mirror the placement of that would be difficult at best.
Back in the day some rural areas used setups like this to extend cell phone service to residents down in valleys. It takes no power at all.
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ask your cellular network provider if they rent or lend out a cell extender device
that will not happen in 99,XX% of all Case. A long time ago we had a Cellphone Shop in the City with thick moist Walls and a brand new Thermal Isolated Glass Window. Gues what happen?
Indoor quite 0 Signals... Thankfully one of the Operator gave us an Repeater who just worked with there Network and dont inter fear other.
Back then it was a former model of that:
https://coiler.com.tw/at-series/
Please note its NOT legal to use them without PERMISSION.
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it should be mentioned, that not every body tissue has the same sensibilty on non-ionizing radiation. In the microwave range, for example on the 2.4GHz ISM band should be taken care to protect eyes; they contain a very high percentage of water, and we all know, why microwage ovens operate on 2,4GHz. When transmitting with my 20W on 2,4GHz in the 95cm dish, there is a strict ban passing within a 4,5m range in front of the dish due to high radiation level.
that's one side of the topic, the other is the following:
clearly those booster, if now for GSM/UMTS/LTE or wifi are not allowed to use; most of those devices don't even meet the specs of spurious emissions.
I got me a 20W wifi booster for my QO100 setup, like expected it came without any LPF. it's of absolutley no interest, if there is a CE label on the device or not. mobile operators pay an enormous amout of money to get the permit to use the frequencies, the requirement they have to meet (and the end user devices too) are strictly regulated. On the wifi frequencies are regulations concerning the maximal emitted radiation, which is in most of europe 100mW EIRP, so even if a booster meets spurious emissions, it exceeds the legal limit quite fast.
if it really goes bad, customs forward such an article to the measurement place of the regulation authority. Not only the article will be gone, but a proper fee for the measurement and maybe a fine can be applied to the buyer. not even as a ham you are safe to buy those articles
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The booster is likely no more powerful at distance than a regular wi-fi access point. Don't worry about it. Your phone may actually reduce its power as well, thinking it is closer to the cell tower than it really is.
I'm not sure about Italty, but for example in the US boosters are "basically" allowed, but must have at least some sort review by the cellular carriers as "ok" to use with their system. They want to limit power, insure quality of signal, etc., as to avoid interference with the rest of the system. There is probably some FCC regulation too (our govering body for RF) likely the Part 15 low power allowance. That being said I'm sure there are lots of crappy imports in use. This is why carriers frown upon them.
We have two types of cellular helping devices, boosters and pico/femto/"small sized" nodes. The boosters do just that, they attempt boost/repeat/amplify the existing recieved over air signals at a location and are often used in rural areas with a directional antenna pointed at town. Results are mixed as they're not terribly intelligent devices, just amplifying what they hear and hoping for the best. The other type are basically little full duplex cell sites in a box with a connection to your home internet for backhaul. These are sold by the individual carriers for use on their specific network only and are generally preferred--provided you have internet!
Now I understand.Thank You very much all for the explanation. I am actually confined in a rural land in the mountains 600 mt. above the sea, locked in grandma's old house with thick walls due to severe COVID restrictions here in North of Italy. We are not allowed to even get out the door. As most of other countries...
Inside the home no way to have even GSM working, (no 4G at all.. only outside in one part of the house I have "decent" 3G signal) Due to particular topographic morphology the house is, even if at height sufficient to see 100km far away in clear days, inside a basin. Trees and a small hill near hides me from the nearest BTS station (it's less than 400meters air line from me but the hill is hiding it. If I overcome the hill I get strong 4G signal and a terrible 150Mbps download link !! ).
The other nearest BTS is in the main town below me at 100mt sea level. I am 500 meters higher. So I think I cannot get the signal from it since as I remember BTS antennas are pointed tilted a little bit down and can't irradiate above the horizon line maybe by some sort of scattering right?
The other three BTS are in the same situation. So I used this booster to amplify a weak signal far away and get decent calls. Not every time, most in Band 8 - 900Mhz sometimes it hops and cannot find anything,
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Well that is and still be illegal. Point.
Look online for an (used, unlocked) Huawei Router with an external Antenna Port.
Back then there where some who have an Phone Port to make calls with.
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If I were you I would put send back the GSM booster unless somebody at your cell network tells you its okay.
Instead, set up a passive system with a directional (I would use a log periodic antenna) connected to an indoor omni antenna, connected with a length of LMR-400 or similar low loss 50 ohm coax cable. KIeep the coax as short as you can.
As it does not transmit this is safe and legal. Point the directional antenna at your nearest, strongest cell site.
This will act like a bidirectional tunnel for the signals. It doesn't have to be strong, just give them a way around the obstacle in both directions.
I would not use non-type accepted devices, you might get in trouble. If that doesn't work, ask your cellular network provider if they rent or lend out a cell extender device of the appropriate, legal kind, or have any other ideas. They will appreciate your coming to them and asking.
I hope that I am making it clear that all this is is two antennas with some coax between them.
Another way to extend signals is using a reflector of some kind to reflect the signals like a mirror, both ways, but like a mirror the placement of that would be difficult at best.
Back in the day some rural areas used setups like this to extend cell phone service to residents down in valleys. It takes no power at all.
CDEV Thank You very much!!, I have already spent money to lay a lossless 50Ohm - 6 GHz BW line (with connectors that has to be with the shielding coax line "combed" :D) from the log periodic antenna at roof to the booster inside the house.
I had already noticed that the signal was increased even with booster powered off.
And in a desperate way during a no-signal-even-with-booster-on moment to I had also tried to lay the coax cable behind the cellphone with no effort. Tomorrow I will try to terminate it with a omnidirectional antenna at the end as you say
Now I am asking You following. Inside our family we have two carriers obviously served by two different BTS located obviously one NORTH and the other WEST with respect to the house. I have two Yagi Antenna, How to combinate them? I have found online a GSM combinator wave guide? thank You
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Well that is and still be illegal. Point.
Look online for an (used, unlocked) Huawei Router with an external Antenna Port.
Back then there where some who have an Phone Port to make calls with.
Of course, thank You for the warning, I will act accordingly. I don't want to get in any troubles. Will trash it and use a passive method CDEV has suggested.
Thank You for the hint of the router. But how to get it working if I have no signal at all inside and outside??
Regards
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Well since you use an Booster you must have an Signal Out there.
You hang an Router on an good directional Antenna who have the right Frequency.
If you want have a more permanent setup you can put the Router into a Water Tide Box and use a short Antenna Cable to the Antenna.
Well looking into Ebay and some local Version of and buy one who you like.
I guess the Speed is not that important for you. Look on the Back of the Router before you buy it if the have a Telefon Line Port. You can use a (cheap) DECT Phone and run arround Home if your Fare include Minutes.
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You could also use an external atenna if your phone has a jack for one. Look for a small rubber plug covering it. If so you'll need a short flexible purpose built coax adapter, which is often called a "pigtail" to connect to the antenna.
I would use a coaxial switch or simply connect whichever one works best at that moment.
You might also want to consider buying a cell phone thats specifically meant to be used stationary in a home, connected to a permanently aimed roof antenna.
The kind of antenna I would use (because it covers multiple cellphone bands) is a log periodic antenna, they are triangular and look like a Yagi but a triangle or arrowhead shape. You can also buy one that meant to be kept indoors that is just a bare PCB antenna, these are very cheap. But it would have to be kept indoors and aimed out of a window, and kept aimed. Keep the coax short because there is a lot of loss at higher frequencies.
Thinking about it a dedicated base-station phone sounds like the best idea. You'd have to use it like a conventional phone, in other words, no portability, but it has the best likelihood of being able to both receive and make outgoing calls. In other words, approximate a wired phone in reliability.
If I were you I would put send back the GSM booster unless somebody at your cell network tells you its okay.
Instead, set up a passive system with a directional (I would use a log periodic antenna) connected to an indoor omni antenna, connected with a length of LMR-400 or similar low loss 50 ohm coax cable. Keep the coax as short as you can.
As it does not transmit this is safe and legal. Point the directional antenna at your nearest, strongest cell site.
This will act like a bidirectional tunnel for the signals. It doesn't have to be strong, just give them a way around the obstacle in both directions.
I would not use non-type accepted devices, you might get in trouble. If that doesn't work, ask your cellular network provider if they rent or lend out a cell extender device of the appropriate, legal kind, or have any other ideas. They will appreciate your coming to them and asking.
I hope that I am making it clear that all this is is two antennas with some coax between them.
Another way to extend signals is using a reflector of some kind to reflect the signals like a mirror, both ways, but like a mirror the placement of that would be difficult at best.
Back in the day some rural areas used setups like this to extend cell phone service to residents down in valleys. It takes no power at all.
CDEV Thank You very much!!, I have already spent money to lay a lossless 50Ohm - 6 GHz BW line (with connectors that has to be with the shielding coax line "combed" :D) from the log periodic antenna at roof to the booster inside the house.
I had already noticed that the signal was increased even with booster powered off.
And in a desperate way during a no-signal-even-with-booster-on moment to I had also tried to lay the coax cable behind the cellphone with no effort. Tomorrow I will try to terminate it with a omnidirectional antenna at the end as you say
Now I am asking You following. Inside our family we have two carriers obviously served by two different BTS located obviously one NORTH and the other WEST with respect to the house. I have two Yagi Antenna, How to combinate them? I have found online a GSM combinator wave guide? thank You
If you want to try you could terminate both the antennas with two omni antennas indoors, but see above for what sounds to me like the best solution. A base station phone thats designed for exactly this kind of condition.
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do I need to stay below the horizontal line sight of the bTS or do I have any change to get it from above?
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You can rotate your Antenna and test the signal strength by 90 Degree on an Router since the Antenna are orientated in different orientation.
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The booster is likely no more powerful at distance than a regular wi-fi access point. Don't worry about it. Your phone may actually reduce its power as well, thinking it is closer to the cell tower than it really is.
While I wouldn't worry about the RF exposure, it's not true to say they're no more powerful than a WiFi access point, the first one I bought* at a flea market had a Hitachi 2W PA module in it, all the ones I've bought since have had 1W or higher PA modules so they're capable of 10 to 20x more power than a (legal) WiFi access point.
As for the OP, I wonder is it possible to enable 'WiFi calling' on the phone (s)?
In low cell signal strength areas (the back of my house for instance) the phone then routes calls over WiFi to the broadband service instead of via cell tower, it works really well for me.
* I bought it because I was curious and it was very cheap, turns out they have a very useful selection of MMIC and other devices that can be re-used as well as coming in pretty nice extruded aluminium heatsink/case, I've never paid more than £3 for them so they're a bargain for the parts.
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You could also use an external atenna if your phone has a jack for one. Look for a small rubber plug covering it. If so you'll need a short flexible purpose built coax adapter, which is often called a "pigtail" to connect to the antenna.
I would use a coaxial switch or simply connect whichever one works best at that moment.
You might also want to consider buying a cell phone thats specifically meant to be used stationary in a home, connected to a permanently aimed roof antenna.
The kind of antenna I would use (because it covers multiple cellphone bands) is a log periodic antenna, they are triangular and look like a Yagi but a triangle or arrowhead shape. You can also buy one that meant to be kept indoors that is just a bare PCB antenna, these are very cheap. But it would have to be kept indoors and aimed out of a window, and kept aimed. Keep the coax short because there is a lot of loss at higher frequencies.
Thinking about it a dedicated base-station phone sounds like the best idea. You'd have to use it like a conventional phone, in other words, no portability, but it has the best likelihood of being able to both receive and make outgoing calls. In other words, approximate a wired phone in reliability.
If I were you I would put send back the GSM booster unless somebody at your cell network tells you its okay.
Instead, set up a passive system with a directional (I would use a log periodic antenna) connected to an indoor omni antenna, connected with a length of LMR-400 or similar low loss 50 ohm coax cable. Keep the coax as short as you can.
As it does not transmit this is safe and legal. Point the directional antenna at your nearest, strongest cell site.
This will act like a bidirectional tunnel for the signals. It doesn't have to be strong, just give them a way around the obstacle in both directions.
I would not use non-type accepted devices, you might get in trouble. If that doesn't work, ask your cellular network provider if they rent or lend out a cell extender device of the appropriate, legal kind, or have any other ideas. They will appreciate your coming to them and asking.
I hope that I am making it clear that all this is is two antennas with some coax between them.
Another way to extend signals is using a reflector of some kind to reflect the signals like a mirror, both ways, but like a mirror the placement of that would be difficult at best.
Back in the day some rural areas used setups like this to extend cell phone service to residents down in valleys. It takes no power at all.
CDEV Thank You very much!!, I have already spent money to lay a lossless 50Ohm - 6 GHz BW line (with connectors that has to be with the shielding coax line "combed" :D) from the log periodic antenna at roof to the booster inside the house.
I had already noticed that the signal was increased even with booster powered off.
And in a desperate way during a no-signal-even-with-booster-on moment to I had also tried to lay the coax cable behind the cellphone with no effort. Tomorrow I will try to terminate it with a omnidirectional antenna at the end as you say
Now I am asking You following. Inside our family we have two carriers obviously served by two different BTS located obviously one NORTH and the other WEST with respect to the house. I have two Yagi Antenna, How to combinate them? I have found online a GSM combinator wave guide? thank You
If you want to try you could terminate both the antennas with two omni antennas indoors, but see above for what sounds to me like the best solution. A base station phone thats designed for exactly this kind of condition.
Yes, thanks: which one would you recommend?
- Small Log Periodic Antenna inside a Plastic Housing Declared 9DbI
- Shorter Yagi same Bandwidth and 13dBi (declared)
- Longer Yagi same Bandwidth and 18dBi (declared)
As of specs I do not fully trust the producer but..
What would be your best choice?
thank You
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:palm: I would buy a Router.
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:palm: I would buy a Router.
Here in Italy we have not yet the ability to route normal calls to VOiP.
The cellphone is mandatory for my wife's work. She is a family doctor and has to support Covid-ill people from home.
Otherwise she has to stay all day 1-mile away and get calls in the car, and it's the begin of winter.
GSM and sometimes 3G signal is the only available, outside the house on the top of the roof.
No other signals are present. Forget 4G. Inside the house I have complete silence.
Do You really think the router will magically restore the low signal and solve all my problems? If yes please tell me the model name and I will buy it immediately.
Thank You.
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:palm: I would buy a Router.
Here in Italy we have not yet the ability to route normal calls to VOiP.
The cellphone is mandatory for my wife's work. She is a family doctor and has to support Covid-ill people from home.
Otherwise she has to stay all day 1-mile away and get calls in the car, and it's the begin of winter.
GSM and sometimes 3G signal is the only available, outside the house on the top of the roof.
No other signals are present. Forget 4G. Inside the house I have complete silence.
Do You really think the router will magically restore the low signal and solve all my problems? If yes please tell me the model name and I will buy it immediately.
Thank You.
It does seem pretty bad that WiFi calling isn't available in Italy, is there perhaps a way you can set up a call diversion from the mobile to a landline?
It seems to no longer be available from Vodaphone but in the UK one company I worked for issued femtocells like these when it was important people had a mobile signal at home:
https://www.vodafone.co.uk/network/calling-features/sure-signal (https://www.vodafone.co.uk/network/calling-features/sure-signal)
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NOPE.
Both option are here unavailable.
We cannot continually transfer the calling to the landline.
We have Vodafone as carrier. I know in UK there is the possibility, also in Germany with Orange.Wi-Fi call here in Italy was never implemented...
Sorry, we are in the land of Pizza and Sun....
:palm: I would buy a Router.
Here in Italy we have not yet the ability to route normal calls to VOiP.
The cellphone is mandatory for my wife's work. She is a family doctor and has to support Covid-ill people from home.
Otherwise she has to stay all day 1-mile away and get calls in the car, and it's the begin of winter.
GSM and sometimes 3G signal is the only available, outside the house on the top of the roof.
No other signals are present. Forget 4G. Inside the house I have complete silence.
Do You really think the router will magically restore the low signal and solve all my problems? If yes please tell me the model name and I will buy it immediately.
Thank You.
It does seem pretty bad that WiFi calling isn't available in Italy, is there perhaps a way you can set up a call diversion from the mobile to a landline?
It seems to no longer be available from Vodaphone but in the UK one company I worked for issued femtocells like these when it was important people had a mobile signal at home:
https://www.vodafone.co.uk/network/calling-features/sure-signal (https://www.vodafone.co.uk/network/calling-features/sure-signal)
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Hey, your issue suddenly became a matter of real importance because of your wife's plight and although you might not realize this, Italy is a real powerhouse when it comes to RF.
Its also an insanely hilly country. Which is part of its allure in many ways but it also demands a technologically innovative, ultra reliable SOLUTION that can be deployed in hours, not in days or months. Empower yourself to do that. Its got to be out there. If you are based in Northern Italy start calling universities, that specialize in literally cutting ege telecommunications and RF technology. tell them we all suggested this here, your problem, there has to be help out there with your name on it.
Isnt there some neighbor who you can "see" in direct line of sight who also has great Internet from a cable connection, or similar? You don't live in some huge valley all by yourselves, like Count Dracula, do you? I didn't think so. You should be able to get a connection through any other person who has reliable Internet who is also line of sight. Even if they are several miles away. This is a frigging emergency. (Just saying) Lives are on the line.
This issue is now a national no a global problem. Your issue is. You deserve an "escalation".
This problem in particular is one people have all around the world, and when doctors and epidemics are involved AS THEY ARE it should get bumped up several notches. Just my lira .02.
By the way, I threw coins into that fountain as a child.
What about satellites? If you keep calls short. (Make liberal use of text messaging which is faster/cheaper)
Just pretend you are in Bananastan.
Here in Italy we have not yet the ability to route normal calls to VOiP.
The cellphone is mandatory for my wife's work. She is a family doctor and has to support Covid-ill people from home.
Otherwise she has to stay all day 1-mile away and get calls in the car, and it's the begin of winter.
GSM and sometimes 3G signal is the only available, outside the house on the top of the roof.
No other signals are present. Forget 4G. Inside the house I have complete silence.
Do You really think the router will magically restore the low signal and solve all my problems? If yes please tell me the model name and I will buy it immediately.
Thank You.
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NOPE.
Both option are here unavailable.
We cannot continually transfer the calling to the landline.
We have Vodafone as carrier. I know in UK there is the possibility, also in Germany with Orange.Wi-Fi call here in Italy was never implemented...
Sorry, we are in the land of Pizza and Sun....
Ah that's a shame, your options would seem to be to break the law, move house or a career change for your wife.
Seems really odd that you can't get a phone divert set up though, that's extremely basic functionality for any cell or phone network, is it perhaps that I've misunderstood and you just don't want to?
One bonus to living in Italy is that the regulations and laws preventing the use of illegal devices like cell boosters seem to be optional and not enforced :)
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Italy's bureaucracy is so notoriously bad and complicated that it seems to create a state of learned helplessness in people after a while.
(Or so at least two Italian engineers who now live in the US both told me).
But even so, there has to be a way. They do get things done after endless fussing, eventually.
Hmm, I just had a thought, I think what the OP is getting at is, this is a TAXATION issue, perhaps one like where the telco is owned and supported by the government, and does not want any other means of communications whatsoever muscling in on their turf.
After all, this is Italy, home of the notorious Mafia.
Just a thought, I don't know what to do in this situation, bizarre as it is. I would try to get scientists into the loop. Maybe science can get a special dispensation from the Pope?
Appeal to a higher power.
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Well it sounds silly but the phone call my wife receives is already diverted!
Patience calls a "simil PBX" and it routes to the doctor's phone actually in service that moment. She cannot make 24hr. a day service.Nor give to everyone her private phone number to call her directly.
She would otherwise be overwhelmed by calls and requests night and day,
Soat the end it would finally be a diverted call from a diverted incoming call. Have tried it already. I-m-p-o-s-s-i-b-l-e. The call simply doesn't get through.
DOH!
Do you in the US have the possibility to divert the call twice?
Regards
NOPE.
Both option are here unavailable.
We cannot continually transfer the calling to the landline.
We have Vodafone as carrier. I know in UK there is the possibility, also in Germany with Orange.Wi-Fi call here in Italy was never implemented...
Sorry, we are in the land of Pizza and Sun....
Ah that's a shame, your options would seem to be to break the law, move house or a career change for your wife.
Seems really odd that you can't get a phone divert set up though, that's extremely basic functionality for any cell or phone network, is it perhaps that I've misunderstood and you just don't want to?
One bonus to living in Italy is that the regulations and laws preventing the use of illegal devices like cell boosters seem to be optional and not enforced :)
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Yes, we call it call hunting, or a "hunt group" where it rings multiple numbers either at the same time, or sequentially, until somebody answers.. Presumably they still don't have that feature which we had here from the beginning of ESS starting in the 1980s.
Honestly, this level of isolation is not really possible, I would think. Unless OP is on some island off the coast or owns their own entire valley or something.
What do mobsters do when they want to be able to speak to their henchmen ? I don't know. But it seems to me as if this, being a matter of substantial importance, OP should not have to go underground, after all lives are being saved and we're not in the midst of warfare, (except against this virus)
Somebody who works with telecom and or community networking a lot would know. Italy is a modern country.
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What about the "analog hole" ?
What do mobsters do when they want to be able to speak to their henchmen ? I don't know. But it seems to me as if this, being a matter of importance, OP should not have to go underground, after all lives are being saved and we're not in the midst of warfare, are we? (except against this virus)
CDEV.
What kind of antenna of the three do you suggest I should use?
Thank You
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It depends on what bands you need to use for your specific application. Your situation cannot possibly be that unique. I suspect that there is a simple answer to your question., What do OTHER emergency personnel do?
CDEV.
What kind of antenna of the three do you suggest I should use?
Thank You
Whatever antenna you get, make sure its a quality one that's appropriate for outdoor mounting and durable enough for professional usage. Because your wife is a professional and this is an important safety essential use. Don't short change yourself or especially, her.
She should not have to sit in a cold car, ever. get a base station phone and mount the antenna on a tall mast on your roof, feed it with LMR-400. Mount and weatherproof the antenna and feedline professionally. get the antenna up as high as is possible, that more than anything else is the key to this situation.
If you need to, buy a tall steel tower so this setup just works.
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they simply live in town. Where the 4G is available.
We cannot move from here in this moment.
It was in order to simply my wife's daily stressful living moment.
Answering inside a car a mile away where she can get calls.
And complicate mine, of course. But this doesn't matter..
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If your wife is a physician, she is a VIP.
A top quality log periodic antenna on top of a tower or tall mast should get you cell phone connectivity to anywhere there is a cell site within line of sight. Even if its several miles away.
There is a program, "SPLAT" that can plot out the terrain you are dealing with using high resolution SAR terrain data for your area.
That will tell you how far you need to go up. You may not need to go up much at all. Here in the US there are cell sites every few meters, seriously. Thousands of them everywhere. Even in the middle of nowhere. Its nuts.
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Do You really think the router will magically restore the low signal and solve all my problems? If yes please tell me the model name and I will buy it immediately.
You put a Huawei Router under your Roof and feet a Antenna Cable with a Antenna on the Rooftop where you have a connection. There are Huawei Router who have 2x (!) Analogue Telephone Port. On this you can put a normal "old" Analogue Telephone and a DECT Device.
If you are insane you can install a PBX on a Rasberry Pi and use an USB to Analogue Telephone Adapter and Voip Phones but that is a future project you dont need think about that now.
to a landline?
If you life in the hell of nowhere forgett about Landline.
We cannot continually transfer the calling to the landline.
Many Operator support to Transfer a Call if a Phone is not available. Ask in an Italian Smartphone Forum if its possible.
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Thanks CDEV,yes she is.
A HERO without overdue, especially in this very difficult situation.
Every day she has to visit ill people without retreating, getting close to the risk to get infected even if wearing FFP2 mask and glasses all day long - a physical fatigue byself, answering phone calls at every moment. A stressful day, every day. She has lost colleagues during last wave, as many of them around the world.
So I am trying my best to help her as much as I can in the daytime.
I will do according to what you suggest.
My concern is only since there are no BTS at my altitude (I am at 600mt above sea level) (other are in the valley (I can clearly see them with my binocular) maybe I have to tilt the antenna pointing it down.
Will let you know
Thanks
If your wife is a physician, she is a VIP.
A top quality log periodic antenna on top of a tower or tall mast should get you cell phone connectivity to anywhere there is a cell site within line of sight. Even if its several miles away.
There is a program, "SPLAT" that can plot out the terrain you are dealing with using high resolution SAR terrain data for your area.
That will tell you how far you need to go up. You may not need to go up much at all. Here in the US there are cell sites every few meters, seriously. Thousands of them everywhere. Even in the middle of nowhere. Its nuts.
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if wearing FFP2 mask and glasses all day long
well the mask must be change very 30min - x Hour! Its insane to wear one for the hole day! :scared:
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if wearing FFP2 mask and glasses all day long
well the mask must be change very 30min - x Hour! Its insane to wear one for the hole day! :scared:
I was meaning wearing not the SAME mask, but working always wearing A (not ONE) mask is a physical stress itself, since the oxigenation is not so good and you tend to inhale part of the same exhaled air (at least a % of the total volume)...
Officially I knew the filtration efficiency of such FFP2 mask was approx. every 4 to 6 hours.
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Whatever it takes to get a phone in the house for your wife so she doesn't have to do that definitely do that.
You should tell her also to look up resveratrol on viruses, (on PubMed) it might help her stay healthy.
It has activity against virus replication, and may be useful as a prophylactic. I keep expecting to see more about this but I have been waiting now almost a year, and so far, very little (go see what is there)
Make sure the resveratrol you buy is good quality. It shouldn't cost much, its quite affordable. get it at a big chain drug store, their generic vitamin products are more likely to be decent than small brands, generally.
Thanks CDEV,yes she is.
A HERO without overdue, especially in this very difficult situation.
Every day she has to visit ill people without retreating, getting close to the risk to get infected even if wearing FFP2 mask and glasses all day long - a physical fatigue byself, answering phone calls at every moment. A stressful day, every day. She has lost colleagues during last wave, as many of them around the world.
So I am trying my best to help her as much as I can in the daytime.
I will do according to what you suggest.
My concern is only since there are no BTS at my altitude (I am at 600mt above sea level) (other are in the valley (I can clearly see them with my binocular) maybe I have to tilt the antenna pointing it down.
Will let you know
Thanks
If your wife is a physician, she is a VIP.
A top quality log periodic antenna on top of a tower or tall mast should get you cell phone connectivity to anywhere there is a cell site within line of sight. Even if its several miles away.
There is a program, "SPLAT" that can plot out the terrain you are dealing with using high resolution SAR terrain data for your area.
That will tell you how far you need to go up. You may not need to go up much at all. Here in the US there are cell sites every few meters, seriously. Thousands of them everywhere. Even in the middle of nowhere. Its nuts.
By all means if you have to look down and can see where the cell site or internet access point is, point it at that.
Antennas are a popular subject here so one way or another we should be able to figure this out. The point I was trying to hammer home is that being a doctor she really needs this connectivity, it should be a high priority for everybody involved in internet or service provision to get it working for you, fast.
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Thanks for all the info here. Ive been trying to boost my LTE signal in my house since I live in the hills the signal sucks (0.8mbps/0.2mbps). I took the advice of CDEV and got myself a decent log periodic antenna in the correct frequency bands and ran a low loss coax cable to a little antenna inside the house and it more than 3x my speeds! (3.8mbps/2.9mbps). I have home internet in the gigabit range but its really shotty and drops often, having 0 signal and no wifi was awful. Glad that this solution worked so well! Thanks everyone
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GSM phone has up to 3 W power and exceed safety limits at short distance to the phone (5-10 cm).
So if you want to use additional power amplifier module, it's better to keep antenna far away from humans.
The same thing is relevant if you're want to use a narrow beam antenna with your phone.
The problem here is that coax cable has some attenuation which is pretty high at 2-3 GHz, so if its attenuation is higher than amplifier/antenna gain, such solution will be useless.
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Regarding the legality and potential interference caused by bidirectional amplifiers (BDAs): these "boosters" are the number one source of interference - by far - in cellular networks. I spent years hunting these down all over the United States and abroad, and I also hold a patent (US11165451B1) on a system for detecting these amplifiers.
The reason BDA's are an issue is mostly the lack of sufficient path loss between the donor and serving antennas - signal that gets coupled between them causes the BDA to oscillate and creates either a very narrow (but high power) "spike" or more often simply raises the noise floor over the entire operating band. In most cases, simply reconfiguring the BDA is enough to prevent this oscillation and allow it to be used without causing interference.
"Self-installs" of BDAs therefore cause the majority of problems, and even in countries where they are nominally "illegally", you can find BDAs everywhere. I thought I saw a lot of BDAs in the United States, but hunting them down in China was like shooting fish in a barrel.
Attached is a whitepaper I wrote on this topic. I also have hundreds of pictures of malfunctioning / misconfigured BDA installations if anyone is interested :)