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Laptop vs iPhone

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Perhaps you are not taking into account that most phones today use composite arrays ...

Unlike laptos...


Just a piece of wire can be a pretty effective antenna if it is tuned properly.

Laptops have more space to put that piece of wire in a nice non obstructed spot (Usually somewhere along the top of the plastic/glass screen bezel). But with the trend of metal laptop cases this might not work so well anymore.

Phones have to contend with squeezing an antenna inside a very compact spot that is close to a lot of other metal parts. Getting an antenna to work reliably in there is a lot trickier, so you see all these funky antenna designs. Some are really good, some not so much. Some are also very sensitive to how you hold the phone as your hand can detune the antenna.

As for WiFi. Yes getting a really good signal is critical for getting anywhere near the theoretical maximum speeds. With the shorter range of 5GHz WiFi this makes it only possible to get near full speed within the same room (unless it is right on the other side of a flimsy drywall and wood wall). So for a lot of cases it might make more sense to just use a Ethernet cable if you really need the speed and you are practically sitting next to the router/ap. Then again reaching 100Mbit over WiFi is plenty usable and you can typically cover a house with a good enough signal for that using about 2 to 4 access points(depends a lot on the size and construction style of the house).

 they are getting better...

highly integrated MIMO chipsets can do a better job than these simple wiring antennas that looped inside the case are always in an horizontal plane while mostly - if not all - routers are using vertical polarization


Rick Law:
Worth checking to make sure:  It could be a limit of the wifi in your laptop, check your machine specs.

My old (Win7) laptop just wont go beyond 300mb, may be your hw/sw on the laptop has a limitation like mine.

E Kafeman:

--- Quote from: PKTKS ---
Mobile phones have much better antennas
--- End quote ---
And any Fiat will overtake a Dodge Hellcat at any redlight. Just as true.

 As antenna designer do I know a lot about needed work to design these kinds of antennas.
 In general will cellphone antennas need much more skilled design work, they can be better from that view, but due to cellphone limitations in size do these antennas perform less good then any decent designed laptop antenna.
 There are no magic way to make an antenna perform better by placing it in a poor location inside a poor cellphone platform from antenna view compared to all antenna space available inside a laptop.
 It is not just two WiFi antennas in a cellphone, there are a number of other antennas, two or more LTE antennas, GNSS, nearfield antennas. Alla these antennas need to be isolated from each other to perform without disturbance from other antennas.
It is not possible in a cellphone, a certain level of disturbance/reduced performance must be allowed due to the restricted space.
 Best antenna location is in top or bottom of the phone as ground plane is longer and more stable from antenna view, and someone speaking in the phone do often not completely cover that part of the phone with hand or head.

 Problem from design view is then to select which antenna/radio system that should have this location reserved? Easy, it will be the LTE antennas.

 GNSS is only of interest in surf-position (one or two hands covering ends of phone) so it will gain somewhat from not being placed in short-ends of the phone.
 The both Wifi antennas are finally placed where any space remain, which seldom are optimal positions from antenna view. One of these both antennas are also used as Bluetooth antenna.

 This gives understanding why WiFi antennas not can perform from best position inside a cellphone, that space is already occupied by other radio system antennas. Space for WiFi antennas are low in priority in a phone.

Even if best antenna positions are reserved for LTE antennas, two or four LTE antennas are common in cell phones, do they perform less good then corresponding laptop or tablet LTE antennas.

There are two important parameters that are easy to measure for LTE antennas:
 1. Efficiency over bandwidth
 2. Mimo
For both these parameters are nature laws against cell phones and a laptop antennas will in most cases be better performing.
 Exceptions exist. An antenna can be designed on a too tight budget which seldom will result in good performance.
 If a tight budget, will a cellphone antenna suffer more then a laptop antenna for natural reasons. It needs more skilled job and more complex design to make a wideband antenna to fit inside a phone then inside a laptop.
 I know because I am doing both these kinds of jobs since many years.
 Do also spend time checking reverse engineer an measuring performance for antennas I not have designed myself.
 Measure always the 5-6 most well-known brand and models, Apple, Samsung, Huawei...

 Average typical values from measurements shows that laptop/tablets have better TIS then cellphones.TIS, Total Isotropic  Sensitivity, is a value of how weak signal that still is usable and is probably the most important parameters to measure.
 Biggest TIS difference is seen in lower frequency bands, 700-900 MHz.

 Comparing among the better designed antenna for phones and laptops is difference is about 6 dB for these lower bands.
 Some even well-known phones have very poor antennas for these lower frequencies.
 That is seldom seen in tablets and laptop antennas, lowest level is high above the worst phone antennas. It is not necessarily poor design, but space in side a phone is limited and priority from marketing view can be that a big camera with several lenses is more important than making that space available for antenna improvement.

 In average is antenna efficiency in modern cell phones lower then it was 10 years ago.
 Reason is rather simple.
 Available suitable antenna space is less today, it is competing with displays and batteries which are taking more amount of available volume inside phone then for ten years ago. As also phone thickness is less today do that also limit available antenna space.

 An ideal dipole antenna will have near 100% efficiency. A such antenna can not be shortened without loosing efficiency, it need to have a length of around 180 mm for 800 MHz and at 2400 MHz is full dipole length 60 mm.
 In many phones is the antenna a fraction of this length while many laptops allows much longer antennas located in screen frame.
 RF absorption
 is a much bigger problem for a cellphone. As phone screen in modern phones are almost covering all available area is there a very limited area available from radiation view as the screen absorbs antenna signal. It is not possible to place antenna away from display or battery which also absorbs RF signals.
Screen frame in a laptop is often much wider, allowing  better distance between antenna and screen.
In a cell phone is normally best antenna location in top or bottom of the phone as it allows for a longer ground-plane, seen from antenna. However is it a real bad antenna position if someone is covering the antenna with hand or head as absorption caused by a hand can be real big.
 A cellphone in normal use is normally handheld so it will always be more or less absorption of antenna signal.
 If not held be hand in head-position is it often held in surf-position, with two hands covering both ends of the phone.
 No good antenna place exist, there will always be  problem due to absorption near different part of the  phone.
 For a laptop is situation the opposite, a hand or head are seldom close to screen frame or cover antenna inside this frame.

 This just a few of the limitations a cellphone suffer from and a laptop not. A cellphone antenna will due to this always be harder to design and implement.
 It is easy to understand that LTE antennas in a tablet in general is better performing then a reduced version of similar antenna with similar needed bandwidth inside a phone.
 For WiFi antenna, will it be given even less optimal place inside a phone, compared to a tablet, as described above.
 However, many laptops and tablets do just have WiFi, no LTE or other kind of antennas, leaving even more available space for WiFi-antennas as they then not need to compete for best antenna location with other radio systems antennas.

--- Quote ---highly integrated MIMO chipsets can do a better job than these simple wiring antennas that looped inside the case are always in an horizontal plane while mostly - if not all - routers are using vertical polarization

--- End quote ---

Several misunderstandings or no understandings at all.  Do not mix chipset job with antenna performance, they are not related, none can replace the other.
 Do you know what mimo is? A single polarization will reduce bandwidth, bitrate will be same as for a single antenna. Remaining router antennas can be removed then, without reduced performance. This is not mimo.

 Basic idea behind WiFi mimo is that each antenna should receive/transmit with a difference in one or both of phase and polarisation.
 Phase difference can be achieved with decent difference in distance between the both antennas relative base station antennas.
 Each antenna should preferably be placed such that it is blind for the second mimo antenna. Is called antenna isolation. 10 dB or more  antenna isolation is wanted but due to that it not is possible to design for good control of polarization and phone size limits max possible distance between the antennas, why 10 dB for all frequencies seldom is possible to design for.

 Reasonable difference in polarization can be achieved by placing an dipole antenna 90 degrees angel to another antenna. As most antennas in a cell phone are designed as monopole structures where all antennas are sharing same ground currents is that a very hard goal to reach a decent wideband polarization isolation or phase difference. It can of course not be compensated at radio chipset for increased bandwidth or improved coverage distance.

 A laptop have here a huge advantage as both sides of the screen frames have greater distance then any distance inside a phone.
 Optimal antenna efficiency needs a full length antenna. For WiFi, 2.4 GHz, is that length around 60 mm. Can not be fitted inside a phone, but no problem at all inside a laptop screen frame.
 To further improve mimo is it an advantage with different antenna polarization.
 As the screen and it its ground plane affect antenna radiation polarization for the relative close placed antenna, will it affect directivity and polarization in opposite direction relative antenna placement at opposite sides of screen and for best polarization difference as close to top corner of screen as possible. This do also give a good place for radiation, decent height and with decent distance from human rf absorbing parts. It is not comparable with a cellphone someone is holding.

--- Quote ---routers are using vertical polarization.
--- End quote ---
That will be a bad WiFi router antenna choice. Trying to avoid mimo and multipath coverage?  However, individual antenna distance and reflection in metallic things inside an apartment and there will a rather even RF coverage in any spot and polarization even if someone tries to avoid it by using very linear polarization for all router antennas.
 Most router antenna are rather cheap in its design and as in this case, is it at least two band antennas, 2.4 and 5 GHz.
 It can still be a good design, even if it is built with cheap material, typical printed on PCB, or a simple stamped metal shape.
 It is however somewhat complicated if it should cover two bands, a single straight wire as monopole is not good enough.

--- Quote ---simple wiring antennas that looped inside the case
--- End quote ---
No that is not how it is made. There are no need for looping WiFi antennas in a laptop.
 A few wires can maybe look very simple if you not know anything about antennas.
 Often is the most simple antenna design the best performing, antenna with highest efficiency.
  If space allows it are in most cases double band dipole antennas to prefer for dual band WiFi, just a few simple wires, as you maybe have seen.
 In some cases can advantage over a cell phone WiFi antenna be taken a step further due the fact that screen frame often is in an upright position and coverage is prefered in horizontal plane. Coverage can then be improved by stacking an additional dipole in screen frame as there often is enough space.
 In a cellphone is no given screen position and there is no space for dual full size wire-antennas and there is very limited control over antenna polarization and antenna distance, why mimo will perform less good compared  to a laptop antenna design.
 Exception, poor design is possible for any product, both laptop and cellphone. Real poor performing antenna among laptop producers are however very rare. A full size blank wire or an antenna created by removing 30 mm of a coaxial braid do often compete well with minimal size wifi antennas placed behind a RF-absorbing screen inside a cell phone.

--- Quote from: PerranOak on March 02, 2022, 04:20:23 pm ---Description:   Intel(R) Wi-Fi 6 AX201 160MHz

--- End quote ---

 Intel AX201 have some problems.
 It is not a slow performing radio but it handles weaker signals real poor and do then drop signal and speed real quick compared to   many other WiFi radios. It is a bit deaf. Should probably need some more development from Intel. Deafness can due to internal self generated noise and can not be fully compensated for by more directive and higher efficiency antennas but it will improve. You is not alone, there are many with similar problem:

A s it is a new laptop is it probably not actual to modify its internal antennas by for example adding option for external antenna connectors or mount two rotatable big Yagi-Uda antennas at top of the laptop lid.
 It can not be excluded that the existing internal antennas are of poor design but budget laptops do usually not select Intel WiFi as many other WiFi-brands are cheaper so I assume that even a certain antenna quality is expected.

 In best case is it a problem with Intel firmware or drivers, which hopefully can be improved, but I doubt it.
 There are a lot of settings in its drivers but nothing will improve transfer speed. Check it anyway.
 For some WiFi radios can TX power be reduced for less coverage but have never seen it for this radio.

 Recommend that you download a software that shows received signal level (RSSI) and also shows other nearby routers.
 RSSI is a negative value showing signal level and measure to radio receiver incoming signal power, mostly in dBm scale. As an example, -30 dBm is a very strong signal and -100 dBm is as weak as it possible can. Different antennas performance and optimal direction can be easy compared using a such software but alternative radios can also be compared.
 I have had good experience using this software for reading RSSI and checking other routers: Similar software can be found for cell phones.
 Here can also be seen if a specific radio channel is occupied by many other routers. Selecting another channel can then increase data transfer speed and make data speed more stable.

 If possible, try to find an USB WiFi adapter to compare performance with your existing Intel ax201. Any USB WiFi adapter from say Broadcom, Qualcomm, Renesas or other well known brands will do as long as it not is an Intel ax chip.  In software compare list length, number of routers. Compare RSSI and the USB adapter shows most likely 10 dB higher values then your Intel 201 if both uses similar performing antenna.


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