ity, charging Country Germany France Italy services, protection against inadvertent message loss, call privacy Preamble length and bureau services. in bits The specification for ERMES is given in Table 45.10. Synchronisation codeword Table 45.10 Specification for ERMES Idle codeword Max batches 24 (or between 42-96) Parameter Value preambles Frequency range 169.4125MHz to 169.8125MHz Transmission 84 (or cycle time in 66-141) Channels 16 channels 25kHz spacing seconds Modulation 4 level (4-PAM/FM) +4687.5 and Number of 3 or 1 +1562.5Hz timeslots Data rate 6.25Kbit/s Longest timeslot 28 (or 12 or 24 Symbol rate 3.125kbaud in seconds 22-47) Error correction 2 bits (30, 18) shortened cyclic Interleaving to provide Message only to a depth of 9 code Table 45.9 Euromessage receiver specification burst error correction words Parameter Value Minimum sensitivity: On body tone only 29uV/m 45.10.2.2 Code format (salty man) The construction of the transmitted code is shown in Figure 45.8. A Minimum sensitivity: tone only free field 32uV/m sixty minute sequence is shown, of which a 1 minute cycle and then Adjacent channel selectivity N 60dB a 12 second subsequence is detailed. Batch I is expanded into its synchronisation, systems information, pager addresses block, and Co-channel rejection N -8dB pager messages block of code words. Intermodulation response N 50dB Battery economy is built into the format at various levels, and to Spurious response rejection: image, above or N 50dB assist current saving, addresses and system information is not inter- below 47-60MHz 87-108MHz 174-230MHz leaved. The pager will be addressed in only one of the sixteen or 470-862Mhz batches (A-P) in a subsequence, enabling it to ignore each of the other fifteen. Once a pager has been addressed within its batch, the All other cases N 60dB corresponding message may be in any of the following batches of that subsequence, or in the following subsequence, up to a point 12 seconds from the start of the batch containing the initial address. The addressed pa