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1. You say that the carrier to interference value in TEMS Investigation actuallyreflects carrier to noise.Can you specify how much of the Signal to noise ratio is attributable to theInterference in the air?ANS:- No, we can't. In case of very low signal strength, C/I rather reflects the signal

to noise ratio (C/N) butwe have no method for differ C/I from C/N. In fact, you could see the C/I as ameasure of C/(I+N+R+A...).I.e. the relationship between the carrier and the sum of all interfering signals. Ofcourse, in most GSM networks,the main part of the interference comes from other base stations(and in the coverage limited case when the signal strength is low, noise).2. Is there a definite link between C/I and S/N, or do we just have to presumethat most of the S/N is caused byC/I?ANS:- See answer on question 1.3. Can you scan (only) the BCCH frequencies, as in, can you get the screen todisplay the C/I or C/N value for apredefined number of frequencies (1...n).ANS:- It is possible to measure C/I in both idle and dedicated mode. In idle mode,you will get a C/I value on the BCCHcarrier in the serving cell. You will not get a value on the neighbours but you can ofcouse simply use the lock on channelfunction and switch serving cell. In dedicated mode, you will get a C/I value for eachfrequency in the hopping list (evenon the BCCH carrier (if included). If you have a non frequency hopping cell, you willget a C/I value on the usedfrequency. It is possible to present the C/I values in four different ways. The methodsworks even in a non frequencyhopping cell (but of course, they will all be very similar).Method 1 . C/I Worst, presents the lowest C/I value (and the corresponding ARFCNvalue) of the frequencies in thehopping list. It is possible to choose index, i.e. the worst, the second worst, the thirdworst etc. It is possible to specifyseveral indexes and monitor them simultaneously.Method 2. C/I Best, presents the highest C/I value (and the corresponding ARFCNvalue) of the frequencies in the

hopping list. It is possible to choose index, i.e. the highest, the second highest, thethird highest etc. It is possible tospecify several indexes and monitor them simultaneously.Method 3. C/I Absolute, presents the C/I value on a specified ARFCN. If the ARFCNis included in the hopping list thevalue is presented. If the ARFCN is not included in the hopping list, nothing isdisplayed. When the frequency appears inthe hopping list (e.g. after an handover to another cell) the C/I value is presented. Itis possible to specify several

ARFCNs and monitor them simultaneously.Method 4. C/I Hopping list, presents the C/I value on a chosen index in the hopping

list. I.e. it is possible to monitor the

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C/I (and the corresponding ARFCN) on e.g. position 1 in the hopping list. It ispossible to specify several indexes andmonitor them simultaneously