Packet Error Rate Wifi
Contents |
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 is the ratio, in percent, of the number of FTAP or FETAP Test Packets not successfully received by the
Packet Error Rate Formula
access terminal (AT) to the number of FTAP or FETAP Test Packets sent to the packet error rate to bit error rate AT by the test set. See Forward Test Application Protocol (FTAP) , Multi-carrier Test Application Protocol and Forward Enhanced Test Application Protocol (FETAP) .
Bit Error Rate Calculation
To perform 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 bit error rate example physical layer subtype is subtype 3) to the access terminal. See Release A Physical Layer Subtype or Release B Physical Layer Subtype to configure 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 packet loss rate definition 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 slots contain Forward Traffic Channel or Control Channel packets (data). The test set fills any empty slots with filler data directed to a random AT other than the AT under test. (0% packet activity means that the source is pulsed off when there is no data to transmit in the slot, and then pulsed on to transmit the MAC and Pilot Channels. This is not supported by the test set.) always implements forced single encapsulation. Forced single encapsulation means that there is always only one valid MAC Packet per Physical Packet, regardless of the size of the Physical Packet. Depending upon data rate, the Physical Packet can be contain between
be challenged and removed. (March 2013) (Learn how and when to remove this template message) In digital transmission, the number of bit errors is the number of received bits of a data stream over a communication channel that have been altered due to noise,
Acceptable Bit Error Rate
interference, distortion or bit synchronization errors. The bit error rate (BER) is the number of bit packet error rate calculator errors per unit time. The bit error ratio (also BER) is the number of bit errors divided by the total number of transferred
Packet Error Rate Wireless
bits during a studied time interval. BER is a unitless performance measure, often expressed as a percentage.[1] The bit error probability pe is the expectation value of the bit error ratio. The bit error ratio can be considered http://rfmw.em.keysight.com/rfcomms/refdocs/1xevdo/1xevdo_meas_cperror_desc.html as an approximate estimate of the bit error probability. This estimate is accurate for a long time interval and a high number of bit errors. Contents 1 Example 2 Packet error ratio 3 Factors affecting the BER 4 Analysis of the BER 5 Mathematical draft 6 Bit error rate test 6.1 Common types of BERT stress patterns 7 Bit error rate tester 8 See also 9 References 10 External links Example[edit] As an example, assume this https://en.wikipedia.org/wiki/Bit_error_rate transmitted bit sequence: 0 1 1 0 0 0 1 0 1 1 and the following received bit sequence: 0 0 1 0 1 0 1 0 0 1, The number of bit errors (the underlined bits) is, in this case, 3. The BER is 3 incorrect bits divided by 10 transferred bits, resulting in a BER of 0.3 or 30%. Packet error ratio[edit] The packet error ratio (PER) is the number of incorrectly received data packets divided by the total number of received packets. A packet is declared incorrect if at least one bit is erroneous. The expectation value of the PER is denoted packet error probability pp, which for a data packet length of N bits can be expressed as p p = 1 − ( 1 − p e ) N {\displaystyle p_{p}=1-(1-p_{e})^{N}} , assuming that the bit errors are independent of each other. For small bit error probabilities, this is approximately p p ≈ p e N . {\displaystyle p_{p}\approx p_{e}N.} Similar measurements can be carried out for the transmission of frames, blocks, or symbols. Factors affecting the BER[edit] In a communication system, the receiver side BER may be affected by transmission channel noise, interference, distortion, bit synchronization problems, attenuation, wireless multipath fading, etc. The BER may be improved by choosing a strong signal strength (unless this causes cross-talk and more bit errors), b
Us Help Follow Us Facebook Twitter Google + LinkedIn Newsletter Instagram YouTube DirectoryNetwork InfrastructureWAN, Routing and Switching LAN, Switching and Routing Network https://supportforums.cisco.com/discussion/12603306/good-snr-high-packet-error-rate Management Remote Access Optical Networking Getting Started with LANs IPv6 Integration and Transition EEM Scripting Other Subjects SecurityVPN Security Management Firewalling Intrusion Prevention Systems/IDS AAA, Identity and NAC Physical Security MARS Email Security Web Security Other Subjects Service ProvidersMetro MPLS Voice Over IP XR OS and Platforms Video error rate Other Subjects Collaboration, Voice and VideoIP Telephony Video Over IP Jabber Clients Unified Communications Applications TelePresence Digital Media System Contact Center Conferencing UC Migrations Other Subjects Wireless - MobilitySecurity and Network Management Wireless IP Voice and Video Getting Started with Wireless WLCCA Other Subjects ServicesCisco ServiceGrid Connected Analytics packet error rate Smart Call Home Smart Net Total Care Operations Exchange Mobile ApplicationsCisco Proximity Cisco Technical Support Online Tools and ResourcesCisco Bug Discussions Technical Documentation Ideas Cisco CLI Analyzer Support Community Help Data CenterApplication Centric Infrastructure Application Networking Intelligent Automation Server Networking Storage Networking Unified Computing Wide Area Application Services (WAAS) Other Subjects Small BusinessNetwork Storage Routers Security Surveillance Switches Voice and Conferencing Wireless Solutions and ArchitecturesBorderless Networks Collaboration Cisco User GroupsSeattle Cisco User Group (SEACUG) Silicon Valley Cisco User Group (SVCUG) Southern California Cisco User Group (SCCUG) Cisco Certifications Cisco.com Idea Center Cisco Cafe Expert CornerTop Contributors Leaderboards Cisco Live! Events Events Community CornerAwards & Recognition Behind the Scenes Feedback Forum Cisco Certifications Cisco Press Café Cisco On Demand Support & Downloads Community Resources Security Alerts Security Alerts News News Video Cisco Support YouTube Cisco YouTube Blogs Technical Documentation Cisco Products Products Service
be down. Please try the request again. Your cache administrator is webmaster. Generated Sun, 23 Oct 2016 21:38:16 GMT by s_wx1085 (squid/3.5.20)