10Mbps TV white spaces trial network planned for South Africa

Ockie

Resident Lead Bender
Joined
Feb 16, 2008
Messages
50,269
Wow....the WC is on a roll hey. You go Helen. Love you long time. :love:

This kind of network sounds interesting. Would like to get more details as it goes along. Hope MyBB will keep up to date with the progress.
 

BravoFox

Well-Known Member
Joined
Aug 2, 2006
Messages
262
"But this white space using is racist!! They should first use up 80% of the black space before they can start using the white space. ":whistling:
 

Bern

Expert Member
Joined
Apr 29, 2010
Messages
2,675
More technical details please!!! Are they using cognitive network technology?
 

XConnect

Active Member
Joined
Mar 25, 2010
Messages
86
Part of the objective of the trial is to test the ability of the radios used to detect interference and also to interrogate a database to determine which frequencies are available for use in that geographic location.
 

evilstebunny

Honorary Master
Joined
Dec 20, 2007
Messages
19,493
Song explained that while speeds of up to 10Mbps may not sound remarkable, it should be noted that the TV white spaces technology does not require line of sight like Wi-Fi alternatives.
10Mbps is way more than Telkom can give me so no complaints there!
 

saffakanera

Expert Member
Joined
Sep 25, 2006
Messages
4,130
The latency would be INSANELY good! When I change my channel from SABC 1 to SABC 2 its pretty much like 10ms! Amazing!
 

ssong

Member
Joined
Jan 21, 2008
Messages
13
Minor correction and additional info

The article may have implied that I am leading this initiative. I'm not. I just sit on steering committee of the project, that's all.

I should also have said that the project is entirely dependent on the good will of ICASA with whom we have not yet applied for a test license for this project. They have been very positive about TVWS so far and very ready to engage but it is still early days.

If you are looking for more information about TVWS, here is a link to a good background article.

http://www.dailywireless.org/2011/08/12/white-space-war/

-Steve
 

Sl8er

Executive Member
Joined
Aug 12, 2010
Messages
7,352
"But this white space using is racist!! They should first use up 80% of the black space before they can start using the white space. ":whistling:
OT:

Whaaahahahahaha! Don't joke hey! :D

Aaaaand we're back on topic....
 

Saajid

Expert Member
Joined
Aug 8, 2008
Messages
4,528
The article may have implied that I am leading this initiative. I'm not. I just sit on steering committee of the project, that's all.

I should also have said that the project is entirely dependent on the good will of ICASA with whom we have not yet applied for a test license for this project. They have been very positive about TVWS so far and very ready to engage but it is still early days.

If you are looking for more information about TVWS, here is a link to a good background article.

http://www.dailywireless.org/2011/08/12/white-space-war/

-Steve
I was about to ask about licensing issues, I guess this answers my main question - we still need the cooperation of ICASA, a major hurdle, as positive as you may want to be.

My other question is how does this affect the migration to DTT and the digital dividend. The way I understand it, TVWS will be making partial use of (future) digital dividend spectrum which will eventually sold/auctioned off in chunks, making TVWS a wasted exercise. Right?
 

LFX

Expert Member
Joined
Jul 26, 2007
Messages
1,851
The latency would be INSANELY good! When I change my channel from SABC 1 to SABC 2 its pretty much like 10ms! Amazing!
This type of broadcast signal works differently... there are no packet requests such as on a wifi network... tv channels are streamed even if you are not tuned in....
 

jackshiels

Expert Member
Joined
Aug 9, 2010
Messages
1,599
This type of broadcast signal works differently... there are no packet requests such as on a wifi network... tv channels are streamed even if you are not tuned in....
So how good is the latency then? Surely requests of some sort have to be made?
 

koeksGHT

Dealer
Joined
Aug 5, 2011
Messages
11,801
The first real reason to pay a TV license to be able to use that spectrum haha
 

Bern

Expert Member
Joined
Apr 29, 2010
Messages
2,675
The article may have implied that I am leading this initiative. I'm not. I just sit on steering committee of the project, that's all.

I should also have said that the project is entirely dependent on the good will of ICASA with whom we have not yet applied for a test license for this project. They have been very positive about TVWS so far and very ready to engage but it is still early days.

If you are looking for more information about TVWS, here is a link to a good background article.

http://www.dailywireless.org/2011/08/12/white-space-war/

-Steve
Thanks for the info!! Very interesting, I hope the project makes some headway and glad to hear ICASA are actually being useful.
 

Saajid

Expert Member
Joined
Aug 8, 2008
Messages
4,528
This type of broadcast signal works differently... there are no packet requests such as on a wifi network... tv channels are streamed even if you are not tuned in....
You are wrong. Yes they are using the same spectrum as TV signals (or the white space in between channels), but that's as far as the similarities go. TV signals are broadcast, in on direction, with no return path. For TVWS technology to be of any use as a data service, it would have to operate on the same basic principals as any other wireless protocol, like WiFi, Wimax, HSPA, iBurst etc. The only real advantage of TVWS is that the spectrum operates at a very low frequency, which means signals travel further and are stronger, are able to penetrate objects and walls much better, and coverage cells can be a lot bigger. Similar to the advantages that Cell C were punting for its HSPA 900 network vs regular HSPA 2100 networks.
 

techead

Honorary Master
Joined
Apr 11, 2008
Messages
12,126
it all sounds good in theory, but what about the uplink? I imagine everything needs to go through Telkom in the end? Unless you have some kind of infrastructure dedicated to this project.

10mbps for users is great, but as we currently see with Telkom... sharing a 155mbit ATM uplink over 5000 users doesnt work
 

Bern

Expert Member
Joined
Apr 29, 2010
Messages
2,675
it all sounds good in theory, but what about the uplink? I imagine everything needs to go through Telkom in the end? Unless you have some kind of infrastructure dedicated to this project.

10mbps for users is great, but as we currently see with Telkom... sharing a 155mbit ATM uplink over 5000 users doesnt work
Surely they could buy some national fibre from DFA/FibreCo or such and then Seacom/Sat3/EASSY/WACS for international - I don't think the point here is about backhaul - that would depend on the various providers - rather testing the last mile effectiveness of the various wireless technologies and spectrum bands.
 

Wimbo

Well-Known Member
Joined
Aug 4, 2004
Messages
119
What are White Spaces?

I was about to ask about licensing issues, I guess this answers my main question - we still need the cooperation of ICASA, a major hurdle, as positive as you may want to be.

My other question is how does this affect the migration to DTT and the digital dividend. The way I understand it, TVWS will be making partial use of (future) digital dividend spectrum which will eventually sold/auctioned off in chunks, making TVWS a wasted exercise. Right?
No. Fair question, but it's not a wasted exercise

Let's introduce a little technical literacy here. The term "TV White Spaces" refers to unused spectrum in the TV bands. The UHF Bands IV and V cover 470 MHz to 860 MHz, which is channels 21 to 68, that is 36 channels, each 8 MHz wide. In the VHF Band III (174 - 230 MHz) , we only use 9 channels (4 - 13, excluding 12). The "Digital Dividend" is 790 - 860 MHz, i.e. channels 61 - 68.

On the Johannesburg Transmitter (Auckland Park Tower, IIRC), Sentech transmits as follows:
SABC1: channel 6, SABC2: 9, SABC3: 13, M-NET: 39, CSN: 43, e-tv: 47.
You will notice that 2 or 3 channels are left unused in each case.These are "white space". This is because analogue technology doesn't handle adjacent channels well. Changing to digital transmission solves this problem - adjacent channels can be used without suffering from adjacent channel interference.

Digital technology gives us another benefit. Currently, SABC1 is transmitted fron 12 transmitters in Gauteng on 11 channels (frequencies). Using digital technology, a Single Frequency Network (SFN) will transmit SABC1 on one channel for the whole of Gauteng, from the same 12 transmitters. In fact, using DVB-T2 (the chosen Digital Terrestrial TV technology), we can fit about 20 TV slots into one frequency channel, so all of the above (SABC1-3, e-tv, etc.) plus a whole lot more will fit into the same 8 MHz frequency channel - called a "multiplex". All of these add up to a huge saving in spectrum.

Does Digital TV also have white space?
Yes, it does.

White Spaces will still exist, although not as much. With both analogue and digital technology, the same frequency can't be used again unless it's several hundred km away. So, even if we were to fill up every available channel with digital multiplexes, there would still be geographical areas where a specific channel isn't used for TV broadcasting, but can be used for low power data transmission over a relatively limited range - less than the 50 km typical for a high power TV transmitter. The concept behind TVWS technology in the digital scenario is to use the spectrum in a "sterilised" area - where it can't be reused for high power TV broadcasting - for low power data transmission and reception.

"High power", BTW, means 10 kW or more. Durban uses a 100 kW transmitter, for example.

So, while there will be significantly less White Space once we have completed the migration to DTT (whenever that will be ...), White Space will still exist, and TVWS technology is still useful.

And yes, ICASA is quite prepared to talk about testing the technology. We are keen to foster several things, one of which is to make more efficient use of spectrum, and another is to explore new ways to provide useful and cost effective broadband connectivity to the public. TVWS technology promises to do both of these.

Steve, please make sure that your people talk to the ICASA spectrum people soon, and submit an application for a test licence before you start transmitting!
 
Last edited:
Top