Comments
For checking RX Level,RX Quality,FER,TA,CSSR,DCR,HSSR
The method and system assign a preferred traffic carrier to each mobile station. During a drive-test, the preferred traffic carrier is assigned to the respective mobile station either originating or receiving a call. In the event of a dropped call, the system attempts to re-establish the call on the preferred traffic carrier to provide continuous monitoring on the same traffic carrier when the call is retried. If the preferred traffic carrier is not available when the BSC or base station assigns a traffic carrier, an alternate traffic carrier can be assigned at the call setup.
Posted by waqqas1
For checking
RX Level
RX Quality
FER
TA
CSSR
DCR
HSSR
Posted by Hash007
Tracking the rapid increase of wireless networks, the wireless industry is increasingly focusing on high quality of service, which is a competitive advantage for a wireless service provider. There are several elements to quality of service: (1) coverage, (2) speech quality, (3) network accessibility (sometime called capacity) and (4) number of dropped calls. One of the tools used to ensure network quality is a drive test.
When a subscriber initiates a call from a mobile unit, a call initiation request is placed on a reverse control channel (RECC). The mobile unit transmits its Mobile Identification Number (MIN), Electronic Serial Number (ESN), and Station Class Mark (SCM), along with the destination telephone number. If a cell cite successfully receives this information, it is forwarded to the MTSO, which may check to see if the subscriber is registered or not, and then assigns the call to a forward and reverse voice channel pair (FVC and RVC) of a public switched telephone line and the conversation commences.
When a subscriber receives a call, the incoming call is received by the MTSO that directs each cell site to transmit on its FOCC a paging message containing the subscriber's mobile identification number (MIN). Each mobile unit constantly monitors the FOCC and when its MIN is successfully detected, the mobile unit transmits an acknowledgement signal on the reverse control channel (RECC). Upon a particular cell site receiving the acknowledgement signal, the MTSO directs that site to simultaneously issue a FVC and a RVC pair. In this manner, the conversation is carried out on a dedicated channel pair separate from the control channels.
Throughout a typical conversation, as the mobile unit travels throughout the service area, the MTSO coordinates and issues numerous "handoffs" which automatically switch subscribers to different voice channels at different cell sites throughout a service area. Handoff decisions are made by the MTSO when the signal strength or quality on the RVC falls below a predetermined threshold level. The carrier periodically adjusts threshold levels with market and system growth, and as call traffic patterns and interference require.
If a new call for a mobile unit comes in and all of the voice channels of the particular cell site receiving the acknowledgement signal are occupied, then the MTSO directs the cell site to issue a directed retry to the subscriber which directs the subscriber to switch to a different control channel on another cell. Depending on the radio propagation effects and the specific location of the mobile unit, this procedure may or may not result in a successful call.
Factors including the performance of the MTSO, specific channel assignments made, relative number and location of the cell sites, and the set signal threshold levels may contribute to degradation in cellular service resulting in poor voice or data quality as well as dropped or incomplete calls.In order to monitor a cellular network's performance, detect fraudulent users, and troubleshoot problems, a service provider must be able to monitor the various control and voice channels. Monitoring real-time signals and signal to interference ratios at various locations in a service area is desirable and will allow a carrier to fine tune the network to improve its quality. A drive test that monitors all channels across multiple base station service areas will provide the necessary data.
Posted by gsmxprt
The Drive Test is basically done to check:
1] Coverage of each sector of that site.
2] Handoff between same site sectors and
neighbouring site's sectors.
3] Access Failures, if any ?
4] Call drops , If any ?
5] Data Throughput.
6] Planned PN being obtained in planned sector
( CDMA )
There are 3 basic types of calls done to test the above factors:
1] Long Call Drive ( for coverage and PN )
2] Short Call Drive ( for access failure , call
drops , call setup success time and ratio )
3] Data Call ( for testing data througput ).
Only if these drive plots show 5 important factors achieving good values , we say that the BTS is radiating properly. The 5 important factors are:
a] EcIo
b] Rx Level
c] Tx Level
d] FFER
e] PN Plot.
Hence , to see the above factors, drive test is imjportant for all BTS's.
Posted by kunalmbhatia
It is basically a method for monitoring the traffic carrier performance of a CDMA carrier in a mobile communication system are provided. The method and system assign a preferred traffic carrier to each mobile station. During a drive-test, the preferred traffic carrier is assigned to the respective mobile station either originating or receiving a call. In the event of a dropped call, the system attempts to re-establish the call on the preferred traffic carrier to provide continuous monitoring on the same traffic carrier when the call is retried. If the preferred traffic carrier is not available when the BSC or base station assigns a traffic carrier, an alternate traffic carrier can be assigned at the call setup. After the call setup procedure is completed, a handoff procedure is initiated to transfer the call from the alternate traffic carrier to the preferred traffic carrier after a predetermined time if the preferred traffic carrier is available.
Posted by sagitraz
Drive test is crucial for testing various fuctions and performances of mobile system/network such as hand-over, interferences between cells, geographical impact on coverage, fading impact in fast moving car.
Posted by ykkim
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