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Coronavirus - how is it/has it affected you?

SocketRocket said:
It uses signal strength to determine the distance.
Click to expand...

If i am right, the only way for a digital device to detect distance is for a 2 way communication between the devices. The distance could, in theory, be measured if it could measure the time it took to send the signal to all the devices in the room, receive it back and decode all the signals received back and measure the time taken from all devices.

It takes 6.6... nano seconds for light to travel 2 metres. Not sure a phone, let's face it, designed for YouTube, tiktok etc would be capable of accurately dealing with that on an app when the phone is dealing with a lot of other apps.
 
KenL said:
If i am right, the only way for a digital device to detect distance is for a 2 way communication between the devices. The distance could, in theory, be measured if it could measure the time it took to send the signal to all the devices in the room, receive it back and decode all the signals received back and measure the time taken from all devices.

It takes 6.6... nano seconds for light to travel 2 metres. Not sure a phone, let's face it, designed for YouTube, tiktok etc would be capable of accurately dealing with that on an app when the phone is dealing with a lot of other apps.
Click to expand...

A phone is smarter than many computers around the world.

It can determine distance

And it is for 15 mins or more... So yes it can easily do it.
 
KenL said:
The golf monthly forum often takes about an hour to tell me a new post has been made on a thread I am following!
Click to expand...

I'd say that's a problem with their server not the phones which are called smart phones for a reason.
 
KenL said:
Please explain how it works and knows you are within 2m rather than just being in bluetooth contact range.
Click to expand...

How does the NHS contact tracing app work?
Contact tracing apps aim to automate the human process by using your smartphone. If successful, an app can alert people about their exposure to people infected with Covid-19 faster than human contact tracers. In theory apps could be a useful tool to quickly get people to self-isolate and limit the spread of the virus. The main issue? Contact tracing apps are new and their effectiveness is largely unproven.
The NHS contact tracing app – like other similar apps around the world – uses a form of low energy Bluetooth to identify phones nearby (these are referred to as encounters). The app uses Bluetooth signal strength between different devices to estimate the distance between people. When someone tests positive for Covid-19 the system can send out alerts to people they have had encounters with. These alerts tell people that they should self-isolate.
Not everyone will be alerted to self-isolate. Only people who have been assessed as being involved in “high-risk” encounters will be notified. High-risk contacts are determined by a few pieces of data that are fed into the app’s risk algorithm – however, generally someone is likely to be at increased risk of contracting the virus if they’ve been within two metres of someone who has tested positive for more than 15 minutes.
For calculating people’s risk scores the app uses distance (via Bluetooth strength), time around a person and details about when their symptoms started. The last of these is based on information that can be inputted into the NHS app. The distances used for calculating risk scores fall into three categories: close (within 0-2 metres), medium (2-4m) or far (further than 4m). These distances are not precise as the actual measurements may vary depending on where you are and where your phone is placed.
The NHS has detailed how its algorithm works and says the distance is measured between people every five minutes. The risk levels are calculated by how long you spend near a person across an entire day. The team behind the app is also able to change the threshold of the risk score – this threshold is based on the R number, the desire to reduce false positives, testing, and “the importance of building public trust in the value of the app”.
Very little personal information is collected by the NHS contact tracing app – it’s free to download from both Apple and Google’s app stores and people don’t need to create an account to use it. There’s no way, or need, for people to provide their name, email address, or telephone number when using the app. The app does not collect people’s location data through GPS.
When the app is opened for the first time it will ask people for a small amount of data and for permission to use a couple of a phone’s features. It asks for the first part of your postcode (SW16, for example) so NHS officials can analyse where the app is being downloaded and provide risk updates for where people live. “This data will be used to understand where the virus is spreading, and how fast it is spreading in different locations,” the NHS says.
The app will also ask for permission to use Bluetooth, so the contact tracing tech can work, and for permission to access a phone’s camera, so people can scan QR codes.
So how does the app work if it doesn’t collect personal data? The system works by using two different codes. Each day it creates a new code for your device which is stored on your phone. Then every 15 minutes it produces another random code that is shared and stored on the devices it communicates with via Bluetooth. All of these codes are deleted after 14 days.
When someone tests positive they can allow their phone to share the daily codes with other app users. The app does this by sharing the codes related to your phone with a central Department for Health and Social Care (DHSC) server that pushes the codes to every other phone with the app installed. Any codes sent to the DHSC server are deleted after 14 days. If there are matches and the risk score is high enough, people will get an alert saying they’ve been in touch with someone who tested positive.
If you book a test via the app it will generate a code that lets people link their test results with the app automatically. These test codes are deleted 24 to 48 hours after they’re created.
The app isn’t just about Bluetooth contact tracing though – this is where it differs from other apps around the world. It also allows people to check their symptoms against a list of current Covid-19 indicators provided by England’s chief medical officer. These include high temperatures, a new continuous cough, changes to sense of smell and taste, and more. Entering symptoms will result in an indication of whether someone will need to self-isolate.
The app also allows people to order a test through the NHS Test and Trace website, offers a countdown of how long people need to self-isolate for if they are doing so, and can provide risk levels in people’s local area (based on the first part of their postcode).
The way the app deviates most from others around the world is through its use of QR codes. Through an in-app camera function, which you will need to give permission to use, it is able to scan QR codes at venues and log where you have been. The government has made it possible for pubs, restaurants and other venues to create their own QR codes through a generator on its site.
Like the rest of the app, QR codes don’t send any information to a central server and they don’t store people’s personal information. They exist as a way for people to remember where they have been, in case they need to tell contact tracers their activities. The QR code function can be turned on and off in the app and it’s possible to delete the records they create.
QR code check-ins are stored on a phone for 21 days – this allows for 14 days for the virus to appear and seven days when people are most likely to be infectious.
 
KenL said:
A digital signal does not have strength, it is either received or it isn't.
A digital radio transmission just goes garbled or cuts out. There's no real in between.

Update.. https://forums.ghielectronics.com/t/bluetooth-measure-distance-between-two-devices/10413
Click to expand...

Also this thread is from 2012

Bluetooth has changed since then

We have different types of Bluetooth
I believe it's why iPhone 6 won't work with the app because it was the one before the roll out of that Bluetooth

In 2012 you could only connect to one thing at once

My headphones can connect to two devices at once now days
 
pauljames87 said:
How does the NHS contact tracing app work?
Contact tracing apps aim to automate the human process by using your smartphone. If successful, an app can alert people about their exposure to people infected with Covid-19 faster than human contact tracers. In theory apps could be a useful tool to quickly get people to self-isolate and limit the spread of the virus. The main issue? Contact tracing apps are new and their effectiveness is largely unproven.
The NHS contact tracing app – like other similar apps around the world – uses a form of low energy Bluetooth to identify phones nearby (these are referred to as encounters). The app uses Bluetooth signal strength between different devices to estimate the distance between people. When someone tests positive for Covid-19 the system can send out alerts to people they have had encounters with. These alerts tell people that they should self-isolate.
Not everyone will be alerted to self-isolate. Only people who have been assessed as being involved in “high-risk” encounters will be notified. High-risk contacts are determined by a few pieces of data that are fed into the app’s risk algorithm – however, generally someone is likely to be at increased risk of contracting the virus if they’ve been within two metres of someone who has tested positive for more than 15 minutes.
For calculating people’s risk scores the app uses distance (via Bluetooth strength), time around a person and details about when their symptoms started. The last of these is based on information that can be inputted into the NHS app. The distances used for calculating risk scores fall into three categories: close (within 0-2 metres), medium (2-4m) or far (further than 4m). These distances are not precise as the actual measurements may vary depending on where you are and where your phone is placed.
The NHS has detailed how its algorithm works and says the distance is measured between people every five minutes. The risk levels are calculated by how long you spend near a person across an entire day. The team behind the app is also able to change the threshold of the risk score – this threshold is based on the R number, the desire to reduce false positives, testing, and “the importance of building public trust in the value of the app”.
Very little personal information is collected by the NHS contact tracing app – it’s free to download from both Apple and Google’s app stores and people don’t need to create an account to use it. There’s no way, or need, for people to provide their name, email address, or telephone number when using the app. The app does not collect people’s location data through GPS.
When the app is opened for the first time it will ask people for a small amount of data and for permission to use a couple of a phone’s features. It asks for the first part of your postcode (SW16, for example) so NHS officials can analyse where the app is being downloaded and provide risk updates for where people live. “This data will be used to understand where the virus is spreading, and how fast it is spreading in different locations,” the NHS says.
The app will also ask for permission to use Bluetooth, so the contact tracing tech can work, and for permission to access a phone’s camera, so people can scan QR codes.
So how does the app work if it doesn’t collect personal data? The system works by using two different codes. Each day it creates a new code for your device which is stored on your phone. Then every 15 minutes it produces another random code that is shared and stored on the devices it communicates with via Bluetooth. All of these codes are deleted after 14 days.
When someone tests positive they can allow their phone to share the daily codes with other app users. The app does this by sharing the codes related to your phone with a central Department for Health and Social Care (DHSC) server that pushes the codes to every other phone with the app installed. Any codes sent to the DHSC server are deleted after 14 days. If there are matches and the risk score is high enough, people will get an alert saying they’ve been in touch with someone who tested positive.
If you book a test via the app it will generate a code that lets people link their test results with the app automatically. These test codes are deleted 24 to 48 hours after they’re created.
The app isn’t just about Bluetooth contact tracing though – this is where it differs from other apps around the world. It also allows people to check their symptoms against a list of current Covid-19 indicators provided by England’s chief medical officer. These include high temperatures, a new continuous cough, changes to sense of smell and taste, and more. Entering symptoms will result in an indication of whether someone will need to self-isolate.
The app also allows people to order a test through the NHS Test and Trace website, offers a countdown of how long people need to self-isolate for if they are doing so, and can provide risk levels in people’s local area (based on the first part of their postcode).
The way the app deviates most from others around the world is through its use of QR codes. Through an in-app camera function, which you will need to give permission to use, it is able to scan QR codes at venues and log where you have been. The government has made it possible for pubs, restaurants and other venues to create their own QR codes through a generator on its site.
Like the rest of the app, QR codes don’t send any information to a central server and they don’t store people’s personal information. They exist as a way for people to remember where they have been, in case they need to tell contact tracers their activities. The QR code function can be turned on and off in the app and it’s possible to delete the records they create.
QR code check-ins are stored on a phone for 21 days – this allows for 14 days for the virus to appear and seven days when people are most likely to be infectious.
Click to expand...

That's great, but I need more than an NHS press release to understand exactly how this "low energy Bluetooth" works.
I've never heard of that before and every website I've read says bluetooth cannot measure distance without lots of other devices sort of triangulating it. I'm just a nerd trying to fully understand how this works really ?
 
Beezerk said:
That's great, but I need more than an NHS press release to understand exactly how this "low energy Bluetooth" works.
I've never heard of that before and every website I've read says bluetooth cannot measure distance without lots of other devices sort of triangulating it. I'm just a nerd trying to fully understand how this works really ?
Click to expand...
Bluetooth 5.1 What’s New?
The main feature that differs Bluetooth 5.1 from other versions of Bluetooth is the direction signal. From the previous versions of Bluetooth like the Bluetooth 5.0, you can only see the distance of your connected devices by how strong the signal is. But Bluetooth 5.1 not just calculate the distance, it also shows the direction to your connected device. There are also some new features added to Bluetooth 5.1 which are stated here
 
pauljames87 said:
How does the NHS contact tracing app work?
Contact tracing apps aim to automate the human process by using your smartphone. If successful, an app can alert people about their exposure to people infected with Covid-19 faster than human contact tracers. In theory apps could be a useful tool to quickly get people to self-isolate and limit the spread of the virus. The main issue? Contact tracing apps are new and their effectiveness is largely unproven.
The NHS contact tracing app – like other similar apps around the world – uses a form of low energy Bluetooth to identify phones nearby (these are referred to as encounters). The app uses Bluetooth signal strength between different devices to estimate the distance between people. When someone tests positive for Covid-19 the system can send out alerts to people they have had encounters with. These alerts tell people that they should self-isolate.
Not everyone will be alerted to self-isolate. Only people who have been assessed as being involved in “high-risk” encounters will be notified. High-risk contacts are determined by a few pieces of data that are fed into the app’s risk algorithm – however, generally someone is likely to be at increased risk of contracting the virus if they’ve been within two metres of someone who has tested positive for more than 15 minutes.
For calculating people’s risk scores the app uses distance (via Bluetooth strength), time around a person and details about when their symptoms started. The last of these is based on information that can be inputted into the NHS app. The distances used for calculating risk scores fall into three categories: close (within 0-2 metres), medium (2-4m) or far (further than 4m). These distances are not precise as the actual measurements may vary depending on where you are and where your phone is placed.
The NHS has detailed how its algorithm works and says the distance is measured between people every five minutes. The risk levels are calculated by how long you spend near a person across an entire day. The team behind the app is also able to change the threshold of the risk score – this threshold is based on the R number, the desire to reduce false positives, testing, and “the importance of building public trust in the value of the app”.
Very little personal information is collected by the NHS contact tracing app – it’s free to download from both Apple and Google’s app stores and people don’t need to create an account to use it. There’s no way, or need, for people to provide their name, email address, or telephone number when using the app. The app does not collect people’s location data through GPS.
When the app is opened for the first time it will ask people for a small amount of data and for permission to use a couple of a phone’s features. It asks for the first part of your postcode (SW16, for example) so NHS officials can analyse where the app is being downloaded and provide risk updates for where people live. “This data will be used to understand where the virus is spreading, and how fast it is spreading in different locations,” the NHS says.
The app will also ask for permission to use Bluetooth, so the contact tracing tech can work, and for permission to access a phone’s camera, so people can scan QR codes.
So how does the app work if it doesn’t collect personal data? The system works by using two different codes. Each day it creates a new code for your device which is stored on your phone. Then every 15 minutes it produces another random code that is shared and stored on the devices it communicates with via Bluetooth. All of these codes are deleted after 14 days.
When someone tests positive they can allow their phone to share the daily codes with other app users. The app does this by sharing the codes related to your phone with a central Department for Health and Social Care (DHSC) server that pushes the codes to every other phone with the app installed. Any codes sent to the DHSC server are deleted after 14 days. If there are matches and the risk score is high enough, people will get an alert saying they’ve been in touch with someone who tested positive.
If you book a test via the app it will generate a code that lets people link their test results with the app automatically. These test codes are deleted 24 to 48 hours after they’re created.
The app isn’t just about Bluetooth contact tracing though – this is where it differs from other apps around the world. It also allows people to check their symptoms against a list of current Covid-19 indicators provided by England’s chief medical officer. These include high temperatures, a new continuous cough, changes to sense of smell and taste, and more. Entering symptoms will result in an indication of whether someone will need to self-isolate.
The app also allows people to order a test through the NHS Test and Trace website, offers a countdown of how long people need to self-isolate for if they are doing so, and can provide risk levels in people’s local area (based on the first part of their postcode).
The way the app deviates most from others around the world is through its use of QR codes. Through an in-app camera function, which you will need to give permission to use, it is able to scan QR codes at venues and log where you have been. The government has made it possible for pubs, restaurants and other venues to create their own QR codes through a generator on its site.
Like the rest of the app, QR codes don’t send any information to a central server and they don’t store people’s personal information. They exist as a way for people to remember where they have been, in case they need to tell contact tracers their activities. The QR code function can be turned on and off in the app and it’s possible to delete the records they create.
QR code check-ins are stored on a phone for 21 days – this allows for 14 days for the virus to appear and seven days when people are most likely to be infectious.
Click to expand...

Thank you for this. If I may ask a question. Does the
phone need to
have " mobile data - On " in the settings. I.e always connected to the internet.
The above says about codes made every 15 minutes etc.
 
Swinglowandslow said:
Thank you for this. If I may ask a question. Does the
phone need to
have " mobile data - On " in the settings. I.e always connected to the internet.
The above says about codes made every 15 minutes etc.
Click to expand...

Shouldn't need to I don't believe as it has nothing to do with your GPS the tracing it's all to do with if your phone comes into contact with another phone via Bluetooth

Bluetooth must be on tho

I'm happy to report been running since it started and my battery hasn't noticed any power drain so I'm happy
 
Old Skier said:
If you can afford a marquee and champagne surely you could manage a phone upgrade.
Click to expand...
I dont need to, I’m using my work phone. besides - no need for technology if pen and paper is just as good.

Nevertheless the possibility of my having to buy a new phone was not mentioned when the app was being sold to us as the answer...Because clearly it never was...either that or those selling the app actually didn’t understand what was required to make it work for all of us. And as explained - something like 80% of us have to have the app for it to be most effective in meeting its Primary objective. But there you go - it was rather oversold - for whatever reason.

Those of us who can should download and use it. Those of us who can’t, can choose to buy a new phone and possibly also an additional carrier contract, or if they can’t afford to do that just stick with manual. Because if manual is just as good for wider community purposes why would anyone buy a second phone - or indeed a first if they don’t have one.
 
Last edited:
KenL said:
If i am right, the only way for a digital device to detect distance is for a 2 way communication between the devices. The distance could, in theory, be measured if it could measure the time it took to send the signal to all the devices in the room, receive it back and decode all the signals received back and measure the time taken from all devices.

It takes 6.6... nano seconds for light to travel 2 metres. Not sure a phone, let's face it, designed for YouTube, tiktok etc would be capable of accurately dealing with that on an app when the phone is dealing with a lot of other apps.
Click to expand...
I cut and pasted this from the app. I can't explain how that works but it's how the apps help explains it.

Risk score calculation
The app uses Bluetooth signal strength between devices to estimate the distance between two people. It estimates the distance for that encounter as one of three levels: Close, Medium and Far.
It is highly likely that encounters identified as “Close” are significantly within 2 metres and that those identified as “Far” are most likely over 4 metres away.
 
Clever stuff, but is it accurate and reliable?
I would not wish to isolate if it mis-calculated me as being close to someone who wasn't close.
Or what if you are outside where we are told there is much less risk?
I suppose at the moment if you have been in the clubhouse or a pub who tests positive you will get a call anyway.
 
KenL said:
Clever stuff, but is it accurate and reliable?
I would not wish to isolate if it mis-calculated me as being close to someone who wasn't close.
Or what if you are outside where we are told there is much less risk?
I suppose at the moment if you have been in the clubhouse or a pub who tests positive you will get a call anyway.
Click to expand...

You can turn off the tracing part for times you are outside.. or if you social distance correct you won't get a false alarm

It's probably as if not more reliable than paper track and trace. Say your friend tests postive. You saw him but only for 5 mins he gives your details to them and they tell you to isolate .. the app will have said not long enough
 
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