Frequent scanning of multiple BLE beacons

Question

I read this thread: nRF51 beacon high frequency scanning and advertising and have similar problem here. 
 Some repost from my electronics.stackexchange.com question 
 
 I have 3 Atmel MCU based BLE scanners,
each uses TI CC2540 based BLE HM-11
module PDF USer
Manual 
chip to scan for the advertise packets
(bluetooth Beacons) around. There are
approx. 10 Beacons at a time around
the scanner sending advertisiment
packets every 100ms. The scanner needs
only Minor, Major and the txPower of
the each beacon. 
 The scanner sends an "AT+DISI" (start
Beacon discovery s. User Manual)
command over serial interface to the
BLE Module and waits for the data
response. 
 Everything works, but the time, until
all data completely arrives takes
around 5 seconds. Since I want to scan
for the Beacons one or two times a
second, I need to improve the scanning
time. 
 
 Beacon properties: 
 
 Possibile avertising interval of 20ms - 100ms 
 Optional: custom interval values (so i can set prime numbers for less collision) 
 Optional: sending on constant frequency (2480MHz) 
 Less payload (I need only Major, Minor and txPower / RSSI) 
 
 Scanner properties: 
 
 Possible to scan 1-3 times a second 
 Possible to scan 10-20 beacons at the time 
 Optional: scanning on the constant frequency (2480MHz) 
 
 Which chip should be used for the beacons? (maybe nRF51822?) 
 Which chip should be used for the scanners? (maybe nRF51?) 
 Is it useful to take nRF51 DK for experiment purposes? 
 Thanks in advance for the answers.

Petter Myhre · Accepted Answer

I would recommend testing with nRF52 DK, our latest and greatest device. 
 With BLE stack, SoftDevice S132 v2, you can: 
 
 Set an advertising interval between 20 ms to 10.24 ms in 0.625 ms steps. The actual minumum advertising interval will vary between 20 ms and 30 ms because of random delay . This is per spec, there are ways to obtain less. 
 Advertise on a single channel, for example channel 39 (2480 MHz) 
 Have a payload between 0 and 31 bytes. 
 Scan continously (as long as the radio is available), or for a certain amount of time 1-3 times a second 
 
 You cannot: 
 
 Scan on a single channel, but there are ways of doing that, see this . 
 
 Can't answer "Possible to scan 10-20 beacons at the time", need more information. The best way to know is to test.

Frequent scanning of multiple BLE beacons

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