Hi, I have a few questions I would like to ask about the Service Mode you can get by accessing it from the dialler.
1) Can you make your phone search for a signal any faster? I notice that if I go to somewhere that has no service it takes a while for the phone to "update" to emergency calls only.
2) What does Dual Mode Improvement really do and is this any good for me as I am on 3 UK (Three)
3) What is IMSI replacement in the Network Control menu?
** Thank you kindly for taking the time to read my post &/or answer any of my questions.
1/ Try this: https://play.google.com/store/apps/details?id=com.mcstealthapps.freshnetwork
2/ A dual-mode phone is a telephone which uses more than one technique for sending and receiving voice and data.
3/ Every mobile phone has the requirement to optimize the reception. If there is more than one base station of the subscribed network operator accessible, it will always choose the one with the strongest signal.
An IMSI-catcher masquerades as a base station and causes every mobile phone of the simulated network operator within a defined radius to log in. With the help of a special identity request, it is able to force the transmission of the IMSI.
Thanks so much for giving the time to answer my questions.
Also, do you know what each of the settings mean for the Diversity Control, I know it's something to do with the phone seeing and utilisting a certain base station but which one would be best for reception gain?
Under: [3] UMTS RF NV > [3] UMTS DIVERSITY CONTROL
I have it currently set to: [1]Diversity on (*)
But what different would it make if i were to set it to: [2]Diversity off [3]Diversity only [4] RxDPM on ?
Thanks once again.
Antenna diversity, also known as space diversity, is any one of several wireless diversity schemes that uses two or more antennas to improve the quality and reliability of a wireless link. Often, especially in urban and indoor environments, there is no clear line-of-sight (LOS) between transmitter and receiver. Instead the signal is reflected along multiple paths before finally being received. Each of these bounces can introduce phase shifts, time delays, attenuations, and distortions that can destructively interfere with one another at the aperture of the receiving antenna.
Antenna diversity is especially effective at mitigating these multipath situations. This is because multiple antennas offer a receiver several observations of the same signal. Each antenna will experience a different interference environment. Thus, if one antenna is experiencing a deep fade, it is likely that another has a sufficient signal. Collectively such a system can provide a robust link. While this is primarily seen in receiving systems (diversity reception), the analog has also proven valuable for transmitting systems (transmit diversity) as well.
Inherently an antenna diversity scheme requires additional hardware and integration versus a single antenna system but due to the commonality of the signal paths a fair amount of circuitry can be shared. Also with the multiple signals there is a greater processing demand placed on the receiver, which can lead to tighter design requirements. Typically, however, signal reliability is paramount and using multiple antennas is an effective way to decrease the number of drop-outs and lost connections.
Antenna diversity can be realized in several ways. Depending on the environment and the expected interference, designers can employ one or more of these methods to improve signal quality. In fact multiple methods are frequently used to further increase reliability.
Spatial diversity employs multiple antennas, usually with the same characteristics, that are physically separated from one another. Depending upon the expected incidence of the incoming signal, sometimes a space on the order of a wavelength is sufficient. Other times much larger distances are needed. Cellularization or sectorization, for example, is a spatial diversity scheme that can have antennas or base stations miles apart. This is especially beneficial for the mobile communication industry since it allows multiple users to share a limited communication spectrum and avoid co-channel interference.
Pattern diversity consists of two or more co-located antennas with different radiation patterns. This type of diversity makes use of directive antennas that are usually physically separated by some (often short) distance. Collectively they are capable of discriminating a large portion of angle space and can provide a higher gain versus a single omnidirectional radiator.
Polarization diversity combines pairs of antennas with orthogonal polarizations (i.e. horizontal/vertical, ± slant 45°, Left-hand/Right-hand CP etc.). Reflected signals can undergo polarization changes depending on the medium through which they are travelling. A polarisation difference of 90° will result in an attenuation factor of up to 34dB in signal strength. By pairing two complementary polarizations, this scheme can immunize a system from polarization mismatches that would otherwise cause signal fade. Additionally, such diversity has proven valuable at radio and mobile communication base stations since it is less susceptible to the near random orientations of transmitting antennas.
Transmit/Receive diversity uses two separate, collocated antennas for transmit and receive functions. Such a configuration eliminates the need for a duplexer and can protect sensitive receiver components from the high power used in transmit.
Adaptive arrays can be a single antenna with active elements or an array of similar antennas with ability to change their combined radiation pattern as different conditions persist. Active electronically scanned arrays (AESAs) manipulate phase shifters and attenuators at the face of each radiating site to provide a near instantaneous scan ability as well as pattern and polarization control. This is especially beneficial for radar applications since it affords a signal antenna the ability to switch among several different modes such as searching, tracking, mapping and jamming countermeasures.
All of the above techniques require some sort of post processing to recover the desired message. Among these techniques are:
- Switching – In a switching receiver, the signal from only one antenna is fed to the receiver for as long as the quality of that signal remains above some prescribed threshold. If and when the signal degrades, another antenna is switched in. Switching is the easiest and least power consuming of the antenna diversity processing techniques but periods of fading and desynchronization may occur while the quality of one antenna degrades and another antenna link is established.
- Selecting – As with switching, selection processing presents only one antenna’s signal to the receiver at any given time. The antenna chosen, however, is based on the best signal-to-noise ratio (SNR) among the received signals. This requires that a pre-measurement take place and that all antennas have established connections (at least during the SNR measurement) leading to a higher power requirement. The actual selection process can take place in between received packets of information. This ensures that a single antenna connection is maintained as much as possible. Switching can then take place on a packet-by-packet basis if necessary.
- Combining – In combining, all antennas maintain established connections at all times. The signals are then combined and presented to the receiver. Depending on the sophistication of the system, the signals can be added directly (equal gain combining) or weighted and added coherently (maximal-ratio combining). Such a system provides the greatest resistance to fading but since all the receive paths must remain energized, it also consumes the most power.
- Dynamic Control – Dynamically controlled receivers are capable of choosing from the above processing schemes for whenever the situation arises. While much more complex, they optimize the power vs. performance trade-off. Transitions between modes and/or antenna connections are signaled by a change in the perceived quality of the link. In situations of low fading, the receiver can employ no diversity and use the signal presented by a single antenna. As conditions degrade, the receiver can then assume the more highly reliable but power-hungry modes described above.
A well-known practical application of diversity reception is in wireless microphones, and in similar electronic devices such as wireless guitar systems. A wireless microphone with a non-diversity receiver (a receiver having only one antenna) is prone to random drop-outs, fades, noise, or other interference, especially if the transmitter (the wireless microphone) is in motion. A wireless microphone or sound system using diversity reception will switch to the other antenna within microseconds if one antenna experiences noise, providing an improved quality signal with fewer drop-outs and noise. Ideally, no drop-outs or noise will occur in the received signal.
Another common usage is in Wi-Fi networking gear and cordless telephones to compensate for multipath interference. The base station will switch reception to one of two antennas depending on which is currently receiving a stronger signal. For best results, the antennas are usually placed one wavelength apart. For microwave bands, where the wavelengths are under 100 cm, this can often be done with two antennas attached to the same hardware. For lower frequencies and longer wavelengths, the antennas must be several meters apart, making it much less reasonable.
Mobile phone towers also often take advantage of diversity - each face (sector) of a tower will often have two antennas; one is transmitting and receiving, while the other is a receive only antenna. Two receivers are used to perform diversity reception.
Cell antennas on an electricity pylon showing two antennas per sector
The use of multiple antennas at both transmit and receive results in a multiple-input multiple-output (MIMO) system. The use of diversity techniques at both ends of the link is termed space–time coding.
Related
I have got the A-GPS option enabled through KaiserTweak and it does make a big difference on Google Maps. My only concern is- what does it cost? Where is it connecting to to get a fix?
I am on T-Mobile UK Web n Walk (unlimited data plan) so if it is connecting through that then there is no issue. I am just always a bit wary about things that I don't understand (quite a lot to be wary about then!) and couldn't find a straight answer anywhere.
Thanks to anyone who can enlighten me!
THe GPS itself is free, the google maps you pay for the data as it downloads the map info. if you use tomtom then you dont pay for anything other than the initial cost of the maps and software if the software didnt already come with the phone
The GPS signal is courtesy of the huge sums spent on military defense over the past couple decades
For real, there is no charge for the GPS tracking proper. What does not come for free are the maps. so Google maps come over the air, meaning you pay via a data plan. If you purchase navigation software, you will pay for maps as well, but you can load them onto a storage card so there would then be no data charges. so esentially a Nav program like Tom Tom/ Garmin/ iGo, once you pay upfront, it is free thereafter (relatively speaking as you will still need to pay for the cost of charging your device battery)
Thanks for your reply. i understand that the GPS itself is free as it is just receiving satellite signals, however the Kaiser also has assisted GPS as an option in KaiserTweaks. From what I understand, this uses info from network masts to give an approximation of where you are. My question is how does this work, or more precisely are there any cost implications that should make me disable the A-GPS option?
A-GPS in terms of the updates that occur from the network are short bursts of data about every 6 days (or almost never if you use active sync regularly as the updates will occur thru the PC's internet connection). If you have any sort of data plan this is a non issue.
The phone just gets some sattellite data to speed up the startup fix when using the built-in GPS.
RemE said:
A-GPS in terms of the updates that occur from the network are short bursts of data about every 6 days (or almost never if you use active sync regularly as the updates will occur thru the PC's internet connection). If you have any sort of data plan this is a non issue.
The phone just gets some sattellite data to speed up the startup fix when using the built-in GPS.
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You are confusing A-GPS with QuickGPS. QuickGPS simply downloads satellite location data via the internet as opposed to getting it directly from the satellites. It's faster to get it from the internet. A-GPS uses cell tower triangulation, though I'm not sure how (or even if) that integrates with the satellite based triangulation when that feature is enabled. Regardless, I wouldn't think A-GPS would cost anything... it doesn't use data, and doesn't use talk time.
No, A-GPS = Assisted GPS = QuickGPS. It's free if you connects by active synch or a wifi connection. It downloads ephemerides of satellites for next 7 days (position of satellites for 6 days and 23 hours exactly) which helps your GPS for the first fix (or cold fix). So with QuickGPS (or A-GPS) you can do the fix in 15-30 seconds max instead of 2-3 minutes without . It's just an help for your GPS ( more informations on http://www.gpspassion.com)
Or you could say that QuickGPS uses A-GPS technology to assist in obtaining quicker GPS fixes. Either way mickey is right.
If you don't use Active Sync or WiFi very much you will use a small amount of data but it is a negligible amount.
mickeydeplage said:
No, A-GPS = Assisted GPS = QuickGPS. It's free if you connects by active synch or a wifi connection. It downloads ephemerides of satellites for next 7 days (position of satellites for 6 days and 23 hours exactly) which helps your GPS for the first fix (or cold fix). So with QuickGPS (or A-GPS) you can do the fix in 15-30 seconds max instead of 2-3 minutes without . It's just an help for your GPS ( more informations on http://www.gpspassion.com)
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Pretty close: The diffference in layman terms: The A-GPS allows your device to remember the last location when you hit a dead spot. This allows the selected GPS program to continue an estimated tracking based on the last recieved location, direction & speed data.
A(ssited) GPS uses no internet data. So there is no charge period. It just uses satelite data.
mickeydeplage said:
No, A-GPS = Assisted GPS = QuickGPS.
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Ok what is the system used by the latest Googlemaps application, and no doubt others, which gives a rough location purely on cell tower data? I understood this to be AGPS.
Shamelessly ripped from Wikipedia...
Assisted GPS
GPS is a satellite based positioning system. Assisted GPS, or A-GPS was introduced to enhance performance. The development of A-GPS was accelerated by the U.S. FCC's E911 mandate requiring the position of a cell phone to be available to emergency call dispatchers. [1]
Conventional GPS then had difficulty providing reliable positions in poor signal conditions. For example when surrounded by tall buildings (as a result of multipath), or when the satellite signals are weakened by being indoors or under trees. Some newer receivers fare better.
In addition, when first turned on in these conditions, some non-A-GPS units may not be able to download the almanac and ephemeris information from the GPS satellites, rendering them unable to function until a clear signal can be received continuously for up to one minute.
An A-GPS receiver can address these problems in several ways, using an Assistance Server:
The Assistance Server can locate the phone roughly by what cell site it is connected to on the cellular network.
The Assistance Server has a good satellite signal, and lots of computation power, so it can compare fragmentary signals relayed to it by cell phones, with the satellite signal it receives directly, and then inform the cell phone or emergency services of the cell phone's position.
It can supply orbital data for the GPS satellites to the cell phone, enabling the cell phone to lock to the satellites when it otherwise could not, and autonomously calculate its position.
It can have better knowledge of ionospheric conditions and other errors affecting the GPS signal than the cell phone alone, enabling more precise calculation of position. (See also Wide Area Augmentation System)
Some A-GPS solutions require an active connection to a cell phone (or other data) network to function, in others [2] [3] it simply makes positioning faster and more accurate, but is not required.
As an additional benefit, it can reduce both the amount of CPU and programming required for a GPS Phone by offloading most of the work onto the assistance server. (This is not a large amount for a basic GPS - many early GPSs ran on 386/16 or similar hardware).
High Sensitivity GPS is an allied technology, that addresses some of the same issues in a way that does not require additional infrastructure. It notably cannot provide instant fixes when the phone has been off for some time, that some forms of A-GPS can.
Coorect. There are several types of Assisted GPS. The native A-GPS on the Kaiser is only for using the data recieved before hitting a dead spot, so your track can continue as estimated.
The recent cell tower & CID assisted GPS programs can take that a step further & in stead of guessing your track based on last known heading & coordinates can also use information from cell towers. Some process this data through servers which keep track of cell tower locations & then provide an estimated fix based on tower triangulation.
GSLEON3 said:
Pretty close: The diffference in layman terms: The A-GPS allows your device to remember the last location when you hit a dead spot. This allows the selected GPS program to continue an estimated tracking based on the last recieved location, direction & speed data.
A(ssited) GPS uses no internet data. So there is no charge period. It just uses satelite data.
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Yep, correct! A-GPS is only a vector forwarding, short intergration of previous data. Only works whilst GPS gives out 'No Sat Data'
It also depends on if you unit is in mode 1 or mode 2 (only ref'd to WM6 GPSmode reg key as it has the handler)...
DTR Control Flow Values.
GPS_NMEA_0183 = 1
GPS_RTCM_104 = 2
Mode 2 (which is default) processes all data through the WM6 handler, Mode 1 will give you RAW data (which should solve the Navigon 'Destination Reached' problem!!!)
A-GPS costs nothing as it is only a calculation, QuickGPS costs only your Internet acces time for its own download and if you have it setup for Activesync, will only use your comps link....
Wow! glad im not the only one who is confused! I get what you're saying about it just calculating position based on last available data, but that doesn't fit with my experience with googlemaps after a hard reset where it came up with a circle of my location despite no gps fix being available.
Thanks to everyone for their help!
The excellent test of the Kaiser here : http://www.gpspassion.com/fr/articles.asp?id=237&page=1 gives a link for the QuickGPS of the Kaiser here : http://www.cdmatech.com/download_library/pdf/gpsonextra_assistance.pdf
mickeydeplage said:
The excellent test of the Kaiser here : http://www.gpspassion.com/fr/articles.asp?id=237&page=1 gives a link for the QuickGPS of the Kaiser here : http://www.cdmatech.com/download_library/pdf/gpsonextra_assistance.pdf
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Brilliant! Thanks for clearing that one up!
mickeydeplage said:
The excellent test of the Kaiser here : http://www.gpspassion.com/fr/articles.asp?id=237&page=1 gives a link for the QuickGPS of the Kaiser here : http://www.cdmatech.com/download_library/pdf/gpsonextra_assistance.pdf
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Now come on!! Where were you hiding when we needed you for reference many threads back??
Good info input...
Assisted GPS or A-GPS uses the mobile phone network to assist the GPS receiver in the mobile phone to overcome the problems associated with TTFF (time to first fix) and the low signal levels that are encountered under some situations.
For A-GPS, the network provides the Ephemeris data to the cell phone GPS receiver and this improves the TTFF. This can be achieved by incorporating a GPS receiver into the base station itself, and as this is sufficiently close in position to the mobile the data received by the base station is sufficiently accurate to be transmitted on to the mobiles. The base station receiver is obviously on all the time, and will be located in a position where it can "see" the satellites.
The information provided can be either the Ephemeris data for visible satellites or, more helpfully the code phase and Doppler ranges over which the mobile has to search, i.e. 'acquisition data'. These ranges can be estimated as the position of the mobile is bounded because it must be within the cell served by the particular base station. This technique is able to improve the TTFF by many orders of magnitude.
Assisted GPS or A-GPS is also used to improve the performance within buildings where the GPS signals are by 20 dB or possibly more. Again by providing information to the GPS receiver in the mobile it is able to better correlate the signal being received from the satellite when the signal is low in strength. Using this technique it is possible to gain considerable increases in sensitivity and some manufacturers have claimed it is possible to receive signals down to power levels of around -159dBm. The base station supplies the receiver with navigation message bits - 'sensitivity data'.
Summary: A-GPS is designed to help get the first fix, but does not improve GPS accuracy; Therefore QuickGPS is a form of A-GPS
To improve the accuracy of the GPS fix, you need Differential GPS (DGPS) - see below
There are many sources of possible errors that will degrade the accuracy of positions computed by a GPS receiver. The travel time of GPS satellite signals can be altered by atmospheric effects; when a GPS signal passes through the ionosphere and troposphere it is refracted, causing the speed of the signal to be different from the speed of a GPS signal in space. Sunspot activity also causes interference with GPS signals. Another source of error is measurement noise, or distortion of the signal caused by electrical interference or errors inherent in the GPS receiver itself. Errors in the ephemeris data (the information about satellite orbits) will also cause errors in computed positions, because the satellites weren't really where the GPS receiver "thought" they were (based on the information it received) when it computed the positions. Small variations in the atomic clocks (clock drift) on board the satellites can translate to large position errors; a clock error of 1 nanosecond translates to 1 foot or .3 meters user error on the ground. Multipath effects arise when signals transmitted from the satellites bounce off a reflective surface before getting to the receiver antenna. When this happens, the receiver gets the signal in straight line path as well as delayed path (multiple paths). The effect is similar to a ghost or double image on a TV set.
Satellite geometry can also affect the accuracy of GPS positioning. This effect is called Geometric Dilution of Precision (GDOP). GDOP refers to where the satellites are in relation to one another, and is a measure of the quality of the satellite configuration. It can magnify or lessen other GPS errors. In general, the wider the angle between satellites, the better the measurement (see GPS Basics slide show for an illustration). Most GPS receivers select the satellite constellation that will give the least uncertainty, the best satellite geometry.
GPS receivers usually report the quality of satellite geometry in terms of Position Dilution of Precision, or PDOP. PDOP refers to horizontal (HDOP) and vertical (VDOP) measurements (latitude, longitude and altitude). You can check the quality of the satellite configuration your receiver is currently using by looking at the PDOP value. A low DOP indicates a higher probability of accuracy, and a high DOP indicates a lower probability of accuracy. A PDOP of 4 or less is excellent, a PDOP between 5 AND 8 is acceptable, and a PDOP of 9 or greater is poor. Another term you may encounter is TDOP, or Time Dilution of Precision. TDOP refers to satellite clock offset. On a GPS receiver you can set a parameter known as the PDOP mask. This will cause the receiver to ignore satellite configurations that have a PDOP higher than the limit you specify.
The nett result of all these error can amount to 10 metres. To provide corrections, Assisted GPS uses data taken from a series on "Known" fixed locations to provide some estimation of the GPS error at a particular location and thus correct it. How this error correction data gets to your PDA depends on the hardware and software involved. Some GPS hardware vendors offer a web/GPRS based service. Differential GPS (DGPS) uses long-wave radio, requiring an additional radio receiver & many transmitting beacons.
WAAS (Wide Area Augmentation System) is a satellite based differential GPS system (DGPS ). A set of satellites constantly transmit correction data for s et of known points. The simplicity of the system is the error correction data is transmitted in the sand frequency spectrum as the GPS data, so not extra radio gear is needed. http://www8.garmin.com/aboutGPS/waas.html gives a reasonable overview of how WAAS works
WAAS is a US based system first tested in 1999; Europe has an equivalent system called EGNOS (European Geostationary Navigation Overlay Service ) operational since July 2005
PS: the Kaiser's GPS receiver has no DGPS functions
As the title suggests, I have very weak Wi-Fi reception with my Diamond. I already set the Wi-Fi to best performance, I was wondering if there was any other setting that might help enhance the reception. I hate to think the unit is defective.
I'm only getting Three bars of signal in the same room, it hovers between four and five within three or so feet, but if I leave the same room it drops to only one bar most of the time, occasionally shooting up or dropping all together. Any help would be appreciated.
Hi
It could be so many factors. Have you changed the channel number to see if that helps What other electronic equipment is close by the router and maybe bluetooth or wireless devices such as telephones etc that my use 2,4ghz frequency (if thats what you are using on 802.11 router. My diamond picks it up just fine.
But bear in mind the overall speed should not really be affected that much for browsing etc if at all
How would I go about changing the channel? Im a bit of a novice with networking.
you would need to change the channel on your route by going into its properties normally something like 192.168.2.1 or 192.168.2.254 etc. But read up if you are unsure so you done mess up any other settings that could disconnect or interrupt your current wireless settings
Me and my friend were arguing whether or not theres a difference between searching for satellites on a 3G/HSDPA and an edge connection.
Is it faster or do they have no correlation at all?
3G/HSDPA/Edge is not necessary at all for gps
gps is a 1 way communication between a passive receiver in a device and a geostationary satellite out in space
3G/HSDPA/Edge is a 2 way communication between a device and a ground based transceiver and antenna setup
in theory you can pull out your sim and throw it in a well
and gps still works
but with assisted gps which x1 support one can get a faster pos by the device getting a rough position from the 3G/HSDPA/Edge connection because they know their own location
I was just planning to Map my Route through MyTracks App from a Flight
But , the problem is , the GSM Network will not work after few thousand feet ...
I want to know How much Altitude, cuts off the GSM Signal , and what are the alternates to get the Network Data working while still flying..
I know we can Pre-cache the Maps but...I want to do this experiment...Has anybody tried ?
unless you are on a small private plane, your phone should not have any of the transmitting antennae turned on (phone, WiFi or Bluetooth) as you'd possibly cause interference issues with flight equipment. Also it would likely breach current safety regulations, hence you are asked to turn such devices off by the flight crew before take-off.
Certain aircraft/carriers allow GSM calls, but use an on-board GSM cell to handle this, not sure if there is additional roaming cost for using this feature.
http://en.wikipedia.org/wiki/Mobile_phones_on_aircraft
@indiandroid
As far as I know, it is not the altitude that cuts the gsm. Other factors are the high speed, and the amount of towers in range. Even though, the phone could connect, it has to switch towers too often to get a steady connection.
If it works though, I wouldn't worry too much about interception, as there is still no case, were phones lead to any problems.
Sent from my GT-N7000 using XDA App
I was playing with my phone during takeoff to see how far I could go before losing signal. I was looking at the GPS, GSM signal, and even barometer sensor.
GSM signal was lost at around 3000 feet.
At 200 mph during takeoff, Google maps had a hard time 'keeping up' with my location. At 400 mph, the GPS satellites had a hard time getting a lock.
At cruising altitude, the cabin pressure drops to around 700 millibars.
It's nothing to do with altitude, it's range from the nearest mast: http://www.youtube.com/watch?v=jpxb7txWZIc&feature=relmfu
I hope I'm never on a flight with any of you. You'd think you'd be able to manage a flight without your transmitters on...
Sent from my superior GT-N7000 using Tapatalk
Forgive me for the small sample size, but I'd gladly appreciate some more data. I have access to 3 Galaxy Nexus models and the one Moto X. By the end of the night I should have an iP5 sample.
My suspicion is telling me something is off on my LTE ping. The 3 GNexes all ping 50-80ms under identical network conditions on my home tower and the Moto X is seldom under 100 (same SIM, same APN, same spot in the house, all within an hour). Obviously you all will have different results since you're testing different towers on different servers, etc. Band 4 with a TMo SIM was pinging pretty low under different network conditions, but this is my only band 4 capable device so I have nothing else to test against.
The lower latency isn't a deal-breaker by any means, but if there's something I can do to fix it, I'd like to. But before beginning I wanted to see if it's more symptomatic of hardware difference in antennas. Since I only have two different makes/models so far, I was hoping one of you lovely folk would be bored enough to test. The tower I've been testing from is band 13, not 4. The Moto X is consistently reporting stronger signal across the board, which is hardly surprising given the difference in hardware age/obsolescence. The ping, however, worries me.
So, any input?
Vandyyy said:
Forgive me for the small sample size, but I'd gladly appreciate some more data. I have access to 3 Galaxy Nexus models and the one Moto X. By the end of the night I should have an iP5 sample.
My suspicion is telling me something is off on my LTE ping. The 3 GNexes all ping 50-80ms under identical network conditions on my home tower and the Moto X is seldom under 100 (same SIM, same APN, same spot in the house, all within an hour). Obviously you all will have different results since you're testing different towers on different servers, etc. Band 4 with a TMo SIM was pinging pretty low under different network conditions, but this is my only band 4 capable device so I have nothing else to test against.
The lower latency isn't a deal-breaker by any means, but if there's something I can do to fix it, I'd like to. But before beginning I wanted to see if it's more symptomatic of hardware difference in antennas. Since I only have two different makes/models so far, I was hoping one of you lovely folk would be bored enough to test. The tower I've been testing from is band 13, not 4. The Moto X is consistently reporting stronger signal across the board, which is hardly surprising given the difference in hardware age/obsolescence. The ping, however, worries me.
So, any input?
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A 50-30ms ping discrepancy is nothing to worry about and well within tolerance for even multiplayer gaming. I don't know if the Moto X is slower or not but if it IS slower than it isn't slower-enough to make a difference in the user experience. You have to be pinging a web site, there is also network congestion to worry about not to mention variances in the load on the tower as just atmospheric conditions constantly changing.
In short... If you're talking about a max variance of 50ms (just for comparison that is about a tenth of the time it takes to blink an eye) it is impossible to say what exactly the cause is. If you really did want to investigate you'd want to ping your devices default gateway, so the first hop for an IP packet as it leaves for the Internet. If you COULD do that then you'd need a LOT of data, so I'd say you'd do multiple samplings from each device over a period of time. If you've got access to the ping command on the device then you could use Android Terminal and instruct ping to do this, I don't remember the exact command right now, but you'd want to ping 3 different times of day, on three different days of the week. Each time you ping, I would do 50 pings.
So each device would end up with 450 data points (50 pings at Time 1, Time 2, and Time 3 for Day 1, Day 2, and Day 3). Then you could reasonably compare them and variances might be visible between the devices. Also, we should look at one other thing, the time span you are talking about we have to take into account the speed of light because in 50ms light (or radio waves) can travel upwards of 9000 miles. This doesn't seem like you'd need to worry about it but you do, because your phone first encodes the ping in a packet for ICMP (an IP type packet). That IP packet then has to get packaged and encoded further to transmit over the LTE radio network. It gets sent to the tower, an unknown distance away. Then it gets decoded and put back into IP form (from LTE signal form) and transmitted along whatever uplink the tower has to its destination.
I suggested doing testing using your default gateway because every single step in the process adds time and adds a layer of uncertainty. If it is going to the default gateway that isn't necessarily the tower, or at the tower. If it is, great. But you don't know where it is physically located, so in 50ms your packet has to travel a lot of distance to get where it is going and then get back to you. Round trip time of 50ms means it probably takes 25ms to get where it is going and 25ms to get back - which is about 3000 miles at the speed of light, so from the middle of the US to the coast (roughly) in perfect conditions, which there never are.
I hope you see my point, though I must admit to enjoying looking up some of the details here. 50ms is not latency you're ever going to notice other than the number on your speed test. However, if you want to test it, you can and without much help either since you have 2 devices to compare. Just run as I suggested above pings to your default gateway (also note if the default gateway is the same on each device) over the cellular network. Compile your data and see what you can see, if you come back with results that show the Moto X is consistently slower than your Nexus device, I would personally love to know about it.
titanshadow said:
A 50-30ms ping discrepancy is nothing to worry about and well within tolerance for even multiplayer gaming. I don't know if the Moto X is slower or not but if it IS slower than it isn't slower-enough to make a difference in the user experience. You have to be pinging a web site, there is also network congestion to worry about not to mention variances in the load on the tower as just atmospheric conditions constantly changing.
In short... If you're talking about a max variance of 50ms (just for comparison that is about a tenth of the time it takes to blink an eye) it is impossible to say what exactly the cause is. If you really did want to investigate you'd want to ping your devices default gateway, so the first hop for an IP packet as it leaves for the Internet. If you COULD do that then you'd need a LOT of data, so I'd say you'd do multiple samplings from each device over a period of time. If you've got access to the ping command on the device then you could use Android Terminal and instruct ping to do this, I don't remember the exact command right now, but you'd want to ping 3 different times of day, on three different days of the week. Each time you ping, I would do 50 pings.
So each device would end up with 450 data points (50 pings at Time 1, Time 2, and Time 3 for Day 1, Day 2, and Day 3). Then you could reasonably compare them and variances might be visible between the devices. Also, we should look at one other thing, the time span you are talking about we have to take into account the speed of light because in 50ms light (or radio waves) can travel upwards of 9000 miles. This doesn't seem like you'd need to worry about it but you do, because your phone first encodes the ping in a packet for ICMP (an IP type packet). That IP packet then has to get packaged and encoded further to transmit over the LTE radio network. It gets sent to the tower, an unknown distance away. Then it gets decoded and put back into IP form (from LTE signal form) and transmitted along whatever uplink the tower has to its destination.
I suggested doing testing using your default gateway because every single step in the process adds time and adds a layer of uncertainty. If it is going to the default gateway that isn't necessarily the tower, or at the tower. If it is, great. But you don't know where it is physically located, so in 50ms your packet has to travel a lot of distance to get where it is going and then get back to you. Round trip time of 50ms means it probably takes 25ms to get where it is going and 25ms to get back - which is about 3000 miles at the speed of light, so from the middle of the US to the coast (roughly) in perfect conditions, which there never are.
I hope you see my point, though I must admit to enjoying looking up some of the details here. 50ms is not latency you're ever going to notice other than the number on your speed test. However, if you want to test it, you can and without much help either since you have 2 devices to compare. Just run as I suggested above pings to your default gateway (also note if the default gateway is the same on each device) over the cellular network. Compile your data and see what you can see, if you come back with results that show the Moto X is consistently slower than your Nexus device, I would personally love to know about it.
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Without actual samples in-hand, I don't think you could have been much more informative. Haha if I may ask: Is this a hobby, career, or degree for you? I may just be bored enough to go through the process you suggested. I need to get a more sturdy nano-micro adapter first. Wouldn't want that bugger to go AWOL during this nonsense.
Vandyyy said:
Without actual samples in-hand, I don't think you could have been much more informative. Haha if I may ask: Is this a hobby, career, or degree for you? I may just be bored enough to go through the process you suggested. I need to get a more sturdy nano-micro adapter first. Wouldn't want that bugger to go AWOL during this nonsense.
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Hobby mostly. Been in computers for a long time now. But, nano-micro-adapter?
titanshadow said:
Hobby mostly. Been in computers for a long time now. But, nano-micro-adapter?
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GNex takes micro-sim, X is nano. Cheap adapters are cheap and there have been plenty of stories of damaged equipment when using half-ass adapters.
Vandyyy said:
GNex takes micro-sim, X is nano. Cheap adapters are cheap and there have been plenty of stories of damaged equipment when using half-ass adapters.
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Oh... I still wouldn't worry about it - the ping times I mean. The latency you'll never notice.