Packet Error
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C.S0033 Tests Performed Using PER How is a PER Measurement Made? Packet Error Rate (PER) is used to test the performance of an access terminal's receiver. PER
Bit Error Rate Calculation
is the ratio, in percent, of the number of FTAP or FETAP bit error rate test Test Packets not successfully received by the access terminal (AT) to the number of FTAP or FETAP Test
Bit Error Rate Example
Packets sent to the AT by the test set. See Forward Test Application Protocol (FTAP) , Multi-carrier Test Application Protocol and Forward Enhanced Test Application Protocol (FETAP) . To perform bit error rate vs snr a packet error rate measurement, the test set sends an FTAP (when current physical layer subtype is subtype 0) or FETAP Test Packet (when current physical layer subtype is subtype 2) or FMCTAP Test Packet (when current physical layer subtype is subtype 3) to the access terminal. See Release A Physical Layer Subtype or Release B Physical Layer Subtype to configure bit error rate pdf the physical layer subtype. Each packet contains 16 FCS (Frame Check Sequence) bit, which provide information about the packet. If the AT is able to decode the packet and the FCS checks (the information relayed by the FCS matches the packet characteristics), then the packet is successfully received. The AT sends one or more FTAP/FETAP/FMCTAP Loop Back Packets to the test set to indicate how many FTAP/FETAP/FMCTAP Test Packets were successfully received for each 16-slot "observation interval" (frame). The AT sends one Loop Back Packet (or more, if needed to convey all of the records) containing a record for each FTAP/FETAP/FMCTAP Test Packet in the observation interval. The Loop Back Packets are queued for transmission on the Reverse Traffic Channel, and the AT must provide buffering for at least 8 FTAP/FETAP/FMCTAP Loop Back Packets. An FTAP/FETAP/FMCTAP Loop Back Packet is generated even if no FTAP/FETAP/FMCTAP Test Packets were received during the 16-slot observation interval. In performing the PER measurement, the test set: always operates with 100% packet activity (see Fixed Settings ). 100% packet activity means that all s
PER (packet error rate). First here is some general information on how BER behaves: -The sensitivity limit is defined as the received
Bit Error Rate Matlab
signal strength gives a BER of 0.1%. - To measure the BER, acceptable bit error rate the amplitude of the received signal is adjusted so that the bit error rate is 1:1000 (0.1 %). Since
Packet Error Rate Formula
we do not have direct accesss to the nRF24L01 demodulated bitstream, the easiest way is to measure the packet error rate (PER), and calculate the bit error rate (from the packet length). http://rfmw.em.keysight.com/rfcomms/refdocs/1xevdo/1xevdo_meas_cperror_desc.html The formula for the packet error rate (PER) is 1-(0.999^N), where N is the number of bits in the data packet. Here is the easy way to get an indication of the sensitivity limit: - You use two evaluation boards and a variable attenuator between the RX and TX board (with SMA connector). Increase the attenuation until you start to loose packets (% https://www.nordicsemi.com/jpn/layout/set/print/Nordic-FAQ/All/How-to-measure-Bit-Packet-Error-Rate-BER-PER-on-the-nRF24L01 depending on the payload size). It is recommended to put either the transmitter board or the receiver board in a shielded box. The total attenuation from the attenuator + cable should now be close to the sensitivity limit, since the output power is 0dBm. Measure the packet error rate by finding the ratio between transmitted and received packets (for instance, transmit 10000 packets, and see how many are received). The sensitivity test should be performed in standard ShockBurst mode (not using ACK/retransmission enabled). The other option is a bit more difficult, but give a more accurate BER: -Setup a RF generator to transmit packages continuously to a RX. The RF generator (and RX) is setup in standard ShockBurst mode, with preamble (10bit), short address (3byte), max payload size (32byte) and no CRC. The MCU on the RX reads all packages received and compare to the original payload. The number of bits wrong give pretty accurate BER. It should be done over at least 10000 bits (256bits in each packet, means >40packets) to get a good indication of the BER. eZ Publish™ copyright © 1999-2016 eZ Systems AS
how do i transfrom "Bit Error Rate" to "frame Error Rate"? Messages sorted by: [ date ] [ thread ] [ subject ] http://mailman.isi.edu/pipermail/ns-users/2006-October/057413.html [ author ] If you plug the values in the formula PER=1-(1-0.001)^8000 = 0.9996658 The above result implies that 99.96% of you packets will have errors and if there are no additional error correction mechanisms, they will be dropped/lost. A BER of 10^-3 is too high and is not practical. For example, in most wireless scenarios, the BER is assumed to be 10^-6. By error rate the way, why are you posting this in ns-users list? Abdul. ªL®õ¨¶ wrote: > for example : > when I give ber=10^-3, packet size=1000bytes, what is PER? > > -----Original Message----- > From: Abdul Jabbar [mailto:jabbar at gmail.com] > Sent: Monday, October 02, 2006 6:24 PM > To: ªL®õ¨¶ > Cc: ns-users at isi.edu > Subject: Re: [ns] how do i transfrom "Bit Error Rate" bit error rate to "Packet Error > Rate"? > > As far as I know, the relationship between BER and PER , assuming that > bit errors are independent and uniformly distributed is, > > PER=1-(1-BER)^N where N is the number of bits. > > However, the above formula is only approximate because in real life > scenarios, the bit errors are not completely independent but may occur > in bursts. Further, the error distribution is also not exactly uniform. > > Hope it helps.... > > Cheers, > Abdul. > > ªL®õ¨¶ wrote: > >> ------------------------------------------------------------------------ >> >> Hi all, how can I transform ¡§Bit error Rate¡¨ to ¡§packet error rate¡¨? >> >> >> >> Is there any formulas for this ? >> >> >> >> Can any body help me? >> >> >> >> >> > > > > > Previous message: [ns] FW: how do i transfrom "Bit Error Rate" to "Packet Error Rate"? Next message: [ns] FW: how do i transfrom "Bit Error Rate" to "frame Error Rate"? Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] More information about the Ns-users mailing list