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Build 5G networks using open-source software, general-purpose hardware (2021)

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Re: Build 5G networks using open-source software, general-purpose hardware (2021)

#11

Post by noselasd »

trustingtrust wrote: post #4
seszett wrote: post #3

Is there anything one can actually do with a home-sized 5G network? As an individual, without being an actual telecom operator and all that.

Campuses like universities could use iot networks in low frequencies which will be much more reliable than Wi-Fi because of range problems.

With lower frequencies comes much lower bandwidth. 5G networks can transmit at much higher power than WiFi, so that's where you get your range at higher frequencie - however that requires licensed spectrum which makes all this a bit harder.

Re: Build 5G networks using open-source software, general-purpose hardware (2021)

#12

Post by ackbar03 »

seszett wrote: post #3

Is there anything one can actually do with a home-sized 5G network? As an individual, without being an actual telecom operator and all that.

What are the rules for broadcasting though? I thought you get hit with a fine without a lisence if you transmit any sort of radio-frequency

Re: Build 5G networks using open-source software, general-purpose hardware (2021)

#13

Post by rkangel »

seszett wrote: post #3

Is there anything one can actually do with a home-sized 5G network? As an individual, without being an actual telecom operator and all that.

The main advantage should be proper base station handoff. If you have a house that can't be covered by a single wifi access point (or an office), then the normal approach is multiple APs with the same SSID. It's a bit of a hack though, you can't guarantee that your device is connected to the one with the best signal, particularly if you move around, and transitioning involves a connection drop.

Proper cellular radio does measurement of signal to surrounding basestations, and seamless handoff. If would have some advantages over wifi in a corporate environment.

Re: Build 5G networks using open-source software, general-purpose hardware (2021)

#14

Post by 7to2 »

ackbar03 wrote: post #12
seszett wrote: post #3

Is there anything one can actually do with a home-sized 5G network? As an individual, without being an actual telecom operator and all that.

What are the rules for broadcasting though? I thought you get hit with a fine without a lisence if you transmit any sort of radio-frequency

Doesn't 5G share some of the frequencies used by normal wifi? IIRC devices implementing one standard even cooperate with devices implementing the other to coordinate frequency use.

Re: Build 5G networks using open-source software, general-purpose hardware (2021)

#16

Post by anfractuosity »

Has anyone ever seen a software defined radio based phone/client out of interest?

Also I've not properly read the paper yet but it mentions a VCTCXO (Voltage Controlled Temperature Compensated Crystal Oscillator), used with some of the SDRs. A while ago I bought a rubidium clock, which I thought may have been decommissioned from a cell tower. I'm curious how important the clock used is, for a cellular system?

Re: Build 5G networks using open-source software, general-purpose hardware (2021)

#17

Post by muyuu »

7to2 wrote: post #14
ackbar03 wrote: post #12

Earlier quoted context omitted.

What are the rules for broadcasting though? I thought you get hit with a fine without a lisence if you transmit any sort of radio-frequency

Doesn't 5G share some of the frequencies used by normal wifi? IIRC devices implementing one standard even cooperate with devices implementing the other to coordinate frequency use.

short answer is no, but the frequencies aren't far off

wifi operates at 2.4Ghz most typically and also at 5Ghz (shorter range but faster)

5G will be ranges of frequencies, depending on jurisdictions, but typically between these two frequencies which are the sweet spot for domestic usage

in the US, 5G carries AFAIK have ranges between 2.5Ghz and just under 4Ghz

in the UK we have EE, O2 and Three operating ranges around 700Mhz besides also having ranges around 3.4Ghz and 3.6Ghz were Vodafone operates too, and those work a lot like US 5G

4G in the UK operates under 2.6Ghz, which is pretty close to wifi also, and LTE is just over 850Mhz or so

basically wifi, 4G and 5G are not strictly higher or lower frequency to each other, it depends on local operators

Re: Build 5G networks using open-source software, general-purpose hardware (2021)

#18

Post by tomn »

rkangel wrote: post #13
seszett wrote: post #3

Is there anything one can actually do with a home-sized 5G network? As an individual, without being an actual telecom operator and all that.

The main advantage should be proper base station handoff. If you have a house that can't be covered by a single wifi access point (or an office), then the normal approach is multiple APs with the same SSID. It's a bit of a hack though, you can't guarantee that your device is connected to the one with the best signal, particularly if you move around, and transitioning involves a connection drop. Proper cellular radio…

This is a bit outdated -- 802.11r fast transitions (FT) allow devices to roam between access points nearly instantly, and 802.11k and v allow access points and clients to exchange scan results, so that access points can move clients to the most appropriate access point.

This does require more than just having multiple access points with the same SSID, and used to be limited to expensive commercial AP brands, but it's quite accessible to consumers these days.

Re: Build 5G networks using open-source software, general-purpose hardware (2021)

#20

Post by detaro »

anfractuosity wrote: post #16

Has anyone ever seen a software defined radio based phone/client out of interest? Also I've not properly read the paper yet but it mentions a VCTCXO (Voltage Controlled Temperature Compensated Crystal Oscillator), used with some of the SDRs. A while ago I bought a rubidium clock, which I thought may have been decommissioned from a cell tower. I'm curious how important the clock used is, for a cellular system?

> I'm curious how important the clock used is, for a cellular system

Very, that's why they bother with things like rubidium holdover clocks. A lot of things depend on precise synchronization, both locally and between multiple towers.

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