Samsung Galaxy S5 - When LTE reception is activated, the phone reception breaks down.

What does the hotline 0800 800 800 think about this?

If necessary, replace the device if there is “suspicion”.

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@schnider wrote:
Furthermore, when LTE is activated and there is almost no telephony reception, when a call comes in, the telephony reception briefly shows all bars again.

What kind of problem is this or have others also observed this?

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It is not possible to make calls with 4G/LTE (today). LTE no longer has a circuit switching mode (CS). In LTE, all data is transmitted in “packet switching” mode (PS). Only VoLTE allows telephone calls in PS mode (future). Today, a telephone call requires a line/connection to be set up, which is only available in 3G/UMTS or 2G/GSM mode. Today, during a telephone call, the mobile phone has to switch from 4G/LTE mode to 3G/UMTS or 2G/GSM mode.

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@schnider wrote:

Either there is only one bar on the cell phone or no reception at all is possible. As soon as I deactivate LTE, i.e. set “Mobile Networks” > “Network Mode” to “WCDMA/GSM”, everything is fine again and the telephony reception shows all the bars.

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The bar display is too imprecise for troubleshooting. The numerical received value is required for troubleshooting. Please the “phone number”:

*#0011#

and publish the RSSI value and the network used (LTE/WCDMA/GSM) here. Alternatively you can go to:

Settings -> Options -> About device -> Status => Signal strength

the RSSI value can be read out. The following applies as a guideline for RSSI:

-40 to -50 dBm -> Extremely strong mobile signal (maximum values ​​for Switzerland)

-50 to -80 dBm -> Very good reception, fast and stable data transfer rates (> 7.2 MBit/s)

-80 to -100 dBm -> Weak to good reception, with slow data transfer rates

-100 to -120 dBm -> Interfered mobile reception or no mobile reception at all

The LTE network can currently only be used for mobile data! When you receive a call or make a call, the S5 automatically switches to 3G or 2G.

The Samsung Galaxy S5 received top marks for its LTE/UMTS and GSM transmission and reception quality in the Connect laboratory test:

http://www.connect.de/produkte/samsung-galaxy-s5-2016706.html

Something is fishy. Am I allowed to bid for the signal strength values ​​of the received LTE, UMTS and GSM signals at an outdoor location?

The measurement results fit (almost) perfectly with the information under:

http://www.lte-provider.info/technik/asu.php

So the Samsung Galaxy S5 works perfectly. For each wireless technology, a different value is used for the ASU calculation:

2G/GSM RSSI

3G/UMTS RSCP

4G/LTE RSRP

The RSSI value is the average of the signal strength over the entire bandwidth of the received signal (bandwidth of GSM: 0.2 MHz; UMTS: 5 MHz: LTE: 5 to 20 MHz) including noise and interference signals from external radio antennas. The RSCP value is the RSSI value adjusted for interference signals and noise and corresponds to the signal strength of the pure UMTS useful signal.

The LTE signal on the 1800 MHz frequency band is most likely broadcast by Swisscom in Zurich Herdern with a bandwidth of 20 MHz. The 20 MHz wide LTE signal consists of 100 individual useful signal carriers. The RSRP value corresponds to the signal strength of a single one of the 100 useful signal carriers. That’s why the RSRP value (LTE) is exactly 20 dB smaller than the RSSI (GSM) or RSCP value (UMTS) from the exact same Swisscom mobile radio antenna. The RSRP value is illustrated very well by the example in the lower half of:

http://laroccasolutions.com/?catid=0&id=78

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@schnider wrote:

So I now put forward the theory that my Samsung Galaxy S5 is not in the limit range of LTE reception at “-100 to -120 dBm -> disturbed mobile reception or no mobile reception at all” (or even further below) for reasons that are still unknown ( automatically) to the UMTS signal, which is then still in the tolerable range at “-80 to -100 dBm -> weak to good reception, with slow Data transfer rates” should be switched.

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Unfortunately, this theory is wrong. Very simplified:

A cell phone receives a 3G/UMTS signal with RSCP -90 dBm just as strongly or well as a 4G/LTE signal with RSRP -110 dBm or a 2G/GSM signal with RSSI -90 dBm. The scale for LTE is simply shifted by 20 dB:

RSRP reception value (LTE only)

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-60 to -70 dBm -> Extremely strong mobile signal (maximum values ​​for Switzerland)

-70 to -100 dBm -> Very good reception, fast and stable data transfer rates (> 10 MBit/s)

-100 to -120 dBm -> Weak to good reception, with slow data transfer rates

-120 to -140 dBm -> Interfered mobile reception or no mobile reception at all

The scale presented in message no. 4 applies to 3G/UMTS (RSCP) and 2G/GSM (RSSI)!

By the way: I recommend using the Android app “Signal level notification”. This app can output the numerical value of the signal strength [dBm] in the status line.