Radio communication arrangements

An arrangement according to any preceding claim, wherein said prior communication was terminated by a communications link failure.

An arrangement according to any preceding claim, wherein said modified page train is truncated, by for example said second device setting a page time-out which ensures that a second frequency sub-train of said page train is not transmitted and said page-time out preferably being set before said modified page train is transmitted.

An arrangement according to any preceding claim, wherein said page scan frequency is shifted on the basis of at least one of clock offset information and a network address relating to said first device.

An arrangement according to any preceding claim, wherein said first device comprises a master unit in a set of master units, and said second device comprises a slave unit, said modified page train comprising part of a series of page trains used by said slave unit to page a plurality of master units in said set and said series of page trains preferably comprising page trains respectively modified such that each starts on an estimate of the page scan frequency of one of said plurality of master units being paged and preferably being truncated such that a respective frequency sub-train thereof is not transmitted.

A arrangement according to any preceding claim, wherein the or each said second device stops paging the or each said first device at the end of a page time-out event, said time-out preferable being settable by or in the or each said second device.

An arrangement according to any preceding claim, including determining, from reception or not of responses to said modified page train from the or each said first device, whether or not the or each said first device is within communications range of said second device.

A communications device suitable for use in an arrangement according to any preceding claim, wherein said communications device is adapted to page at least one further communications device using a page train centered around a page scan frequency of said further communications device, wherein, under predetermined circumstances following prior communication between said devices, said communications device is adapted to transmit a page train which has been modified to start on a frequency shifted to correspond to said estimate.

A method of operating a communications arrangement comprising first and second communications devices, said first device being adapted to enter into a page scan state in which it is receptive to transmissions on a particular page scan frequency and said second device being adapted to transmit a page train centered around an estimate of said page scan frequency of said first device, the method including said second device transmitting, under predetermined circumstances following prior communication between said devices, a page train which has been modified to start on a frequency shifted to correspond to said estimate.