A.3 Scenario 2: PLMN and CTS-GFL have locally no common frequency

3GPP43.052GSM Cordless Telephony System (CTS), Phase 1Lower Layers of the CTS Radio Interface, Stage 2Release 17TS

In this section we consider the locations where the BA list of any covering cell and the GFL of any covering CTS-FP have no common frequency.

This section corresponds to the typical operation of GSM and CTS in shared band with appropriate GFL depending on CTS-FP location.

A.3.1 Cell Selection

A.3.1.1 GSM-MS has no BA list stored on the SIM

The GSM-MS behaviour is same as in scenario 1 (see subclause 2.1.1). The impact on GSM-MS is an additional delay of maximum 0,5 sec per CTS frequency on which synchronisation is attempted.

A.3.1.2 GSM-MS has a stored BA list on the SIM (optional)

The GSM-MS attempts first to camp on a cell with frequency in that BA list.

Either no CTS-FP transmits on any frequency in the stored BA list, and impacts are similar to scenario 1 (see subclause 2.1.2). This is typically the case when the GSM-MS did not move since BA list was stored.

Or one or more CTS-FPs transmit on frequency in the stored BA list at the MS current location. Then the GSM-MS will perform power measurements on CTS frequencies and possibly attempt to synchronise to them. The impact on GSM‑MS is an additional delay of maximum 0,5 sec per CTS frequency on which synchronisation is attempted.

A.3.2 Cell reselection

A.3.2.1 GSM-MS camping on its home PLMN

When camped on a cell, the GSM-MS shall monitor frequencies from the BA list provided on the BCCH.

Since the BA list and GFL have locally no common frequency, the GSM-MS never monitors CTS-FP frequency. CTS deployment has no impact on GSM-MS behaviour.

A.3.2.2 GSM-MS camping on a visited PLMN in home country

When on a VPLMN in home country, the GSM-MS has in addition to search its HPLMN with a period T, T from 6 minutes to 8 hours (this parameter is normally on the SIM, otherwise default value is 30 minutes). So every T minutes the GSM attempts to access its HPLMN. In this case, impact on GSM-MS is, as in subclause 2.1.1., an additional delay of max 0,5 sec per CTS frequency on which synchronisation is attempted.

A.3.3 Handover

When in connected mode, the GSM-MS shall monitor frequencies from the BA list provided on the SACCH.

Since the BA list and GFL have locally no common frequency, the GSM-MS never monitors any CTS-FP frequency. CTS deployment has no impact on GSM-MS behaviour.