PCR2 FAQ

use if,

• you need a robust and maintenance free solution
• there are no cameras allowed due to privacy regulations such as the European GSPR
• you have a LoRaWAN network
• you need outdoor people counter (go for PCR2-OD and PCR2-ODS)
• if you can ensure that people walk behind each other and not next to each other.

Because of the following reasons, PCR2 is not recommended

Occupancy in a room
If you need the exact headcount of persons entering a building or room, it’s better to go for another technology like turnstiles or cameras with face-matching technology as PCR2 is not able to count people walking in rooms side by side.

Battery powered
Many people think of LoRaWAN devices as battery-powered sensors with years of battery life. LoRaWAN data transmission is in fact very energy efficient.
Unfortunately, the integrated radar sensor needs too much energy to get a useful operating time with batteries. Therefore, all PCR2-IN are externally powered. However, we do have solar powered devices for outdoor use.

The LoRaWAN® specification is a Low Power, Wide Area (LPWAN) networking protocol designed to wirelessly connect low energy devices to the internet in regional, national or global networks, and targets key Internet of Things (IoT) requirements such as bi-directional communication, end-to-end security, mobility and localization services. Read more...

This is a connected device (sensor). The LoRaWAN® connection is used to transmit data to a server at regular intervals having a real time coverage of the traffic situation.

No.

There are professional LoRaWAN® Networks Providers with fully managed offerings including support. Ask Google to find such a provider in your area.

It is possible to run private LoRaWAN® networks including own LNS and Gateways. Although we do not recommend it and won't be able to support it. If there is no professional provider in your area this might be the only option to operate TCR traffic counters.

Take following advice based on our experiences:

• Use only quality LoRaWAN Gateways from famous manufacturers such as Tektelic or Kerlink.
• Use Loriot Free Community Public Server to get started. Later you can switch to Professional Offering. Loriot.io is good software. We did not see major issues so far.
• Use ThingPark®. ThingPark® Enterprise is an IoT connectivity management solution allowing to deploy a dedicated and fully controlled LoRaWAN® network for a fast use case enablement.

We do not recommend using community operated LoRaWAN® networks for professional applications. (Would you like to fly to mars with a RaspberryPI controlled rocket!?)

Why we do not recommend it?

• There is nobody you can contact except "the community".
• Coverage of community networks is not guaranteed. Gateways can be switched on or off at any time changing the whole coverage map.
• Usually these networks are based on very limited hardware.
• Limited knowledge on building wireless networks including the selection of suitable locations and antenna optimization.

Technically yes, but we do not recommended it.

The Things Network (TTN) is the free community network, that’s mainly operated by TTI on best effort.

There is a Fair Use Policy which limits the uplink airtime to 30 seconds per day (24 hours) per node and the downlink messages to 10 messages per day (24 hours) per node.

You may get support from volunteers, at the TTN forum but they cannot access the network servers to analyze or fix anything.

Due to TTN is very limited we do not recommend using it together with our products because it restricts the functional potential.

We have a public repository where you can download a payload decoder code examples as a starting point to write your own decoder.

please click here for the answer.

For the initial configuration we recommend using the PPX Setup Tool.

Alternatively, the command line interface CLI can also be used. For large deployments, it would even be worthwhile to write a few Python scripts using the CLI to configure the devices automatically.

When the devices are rolled out, the settings can be changed remotely via LoRaWAN® Downlinks.

You find the LoRaWAN® Keys Slip on the inside of the box. This slip is printed out during the production of the device and contains device-specific data.

Starting with PCR2 Firmware V4.1 you can lock the settings with a PIN code. See the CLI Documentation for details.

PCR2 are bidirectional people counters that must be placed to the side of a walkway or overhead.

• RTL means from right-to-left When a person walks past the sensor coming from the right.
• LTR means from left-to-right When a person walks past the sensor coming from the left.

The directional indications are meant from the viewer's perspective towards the LEDs.

Principle of counting
PCR2 are bi-directional sensors that count people walking on a virtual line.

Accuracy considerations
If you can count people in a relatively narrow passage the accuracy is nearly 100% due to the fact persons are separated from each other. The Radar beam is not able to look 'through persons'. So people walking in pairs (side-by-side) will be counted as one, resulting in an accuracy of 50%.

If Windows driver allocation fails you might re-install the driver with the Zadig tool.

Zadig is a Windows application that installs generic USB drivers, such as WinUSB, libusb-win32/libusb0.sys or libusbK, to help you access USB devices. It is also useful to uninstall broken drivers.

1. Download and install Zadig.
2. Start Zadig and choose Options>List All Devices to show all available USB devices
3. Connect your device while holding the BOOT button (Start DFU Mode)
4. Look for a device with name "STM32 BOOTLOADER" or "STM32 Device in DFU Mode"
5. Select "WinUSB" and press the "Replace Driver" button. Zadig removes the installed driver and installs the generic WinUSB driver.
6. Try the DFU again

RSSI and SNR must be considered to evaluate the radio link quality. You can find these levels somewhere on your LoRaWAN Network Server.

• RSSI is the received signal strength
• SNR is the signal noise rate and give indication on the ambient noise level

• Radio link can be considered has GOOD when RSSI > -115dB and SNR > -7dB
• Radio link is BAD (range limit) when RSSI <= -120 dB or SNR <= -13dB

Between this 2 cases

If RSSI is good (> -115dB) but SNR bad (<= -13dB)

It means that the environment of the gateway is very noisy. SNR must be checked during many days to be sure that the radio link is enough stable to receive all messages.

If RSSI is bad ( <=-120dB) but SNR good (> -7dB)

It means that device is probably far away from the gateway.

If you see error messages like _Downlink transmission failed with result TOO_EARLY, your gateway may suffer from a slow internet backhaul.

You might schedule a time delay in TTN's gateway settings. The better option of course is looking for a better internet connection.

Step 1: Check LoRaWAN Region Setting

Please check the LoRaWAN Region of your device. Connect your device via an USB Cable and open PPX. You should find the LoRaWAN Region String in the device type plate.

See Users Manual for a description on how to change the LoRaWAN Region.

Step 2: Check LoRaWAN Keys

Check if you entered the right keys by using PPX.

Step 3: Check LoRaWAN Connectivity Settings

PCR2 with Firmware V4.x.x uses the following network parameters by default:

• LoRaWAN® 1.0.3
• Class A
• OTAA
• Confirmed Uplinks
• ADR On
• LinkChecks enabled

These settings need to mach the settings on your LNS

Step 4: Check Link Quality

If your see Join Requests in your LNS but device still does not join you may have one of the following issues:

• The device is located in a very noisy area and not receiving ACK messages from the gateway. Try to displace the device or increase TX power on the gateway

• Check Signal Quality of ACK by using the LoRaWAN Status View in PPX

• Displace the gateway

DevNonce is a counter starting at 0 when the end-device is initially powered up and incremented with every Join-Request. A DevNonce value SHALL never be reused for a given JoinEUI value.

If you see an error message like "DevNonce is too small" you should try the following:

1. Clear the NV Context Memory of the device

Reset the devices context memory (NVMemory) by using the CLI command save

2. Reset used DevNonces

TTN V3

When using TTNv3 you will find a button Reset used DevNonces under General Settings>Join Settings

This will set the expected DevNonce counter back to zero, allowing the join procedure to start from scratch.