Distribution of system access information in wireless communication system

An access node for operation in a cell of a wireless communication network, the access node comprising:

• processing circuitry;
• and
• memory containing instructions executable by the processing circuitry whereby the access node is operative to:
• alternate between two or more operating modes including a normal power mode and low power mode;
• transmit in the normal power mode, first system access information with a first information density to wireless terminals in a coverage area of the access node;
• transmit, in the low power mode, second system access information with a second information density to the wireless terminals in the coverage area of the access node, the second information density being lower than the first information density, and wherein to transmit the second system access information in the low power mode, the access node is configured to transmit initial system information that comprises:
• less than all the system information transmitted in the normal power mode;
• and
• an access allowed flag indicating whether wireless terminals are allowed to transmit access requests for additional system access information to a cell served by the access node after acquiring synchronization;
• receive, while in the low power mode, an access request for the additional system access information from one of the wireless terminals, wherein the access request indicates downlink resources on which the access node is to transmit the additional access system information;
• and
• responsive to the access request and while remaining in the low power mode, send the additional system access information on the downlink resources indicated in the access request to the access requesting wireless terminal.

A method implemented by a wireless terminal, the method comprising the wireless terminal:

• starting a timer;
• monitoring a downlink channel for initial system access information transmitted by an access node on the downlink channel, wherein the initial system information comprises an access allowed flag indicating whether the wireless terminal is allowed to transmit access requests for additional system access information to a cell served by the access node after acquiring synchronization;
• in response to the timer expiring before detection of the initial system access information, sending an access request to the access node on an uplink channel to request additional system access information, wherein the access request indicates downlink resources on which the access node is to transmit the additional access system information;
• and
• receiving, responsive to the access request, the additional system access information from the access node on the downlink resources indicated in the access request.

A wireless terminal, comprising:

• processing circuitry;
• and
• memory containing instructions executable by the processing circuitry whereby the wireless terminal is operative to:
• start a timer;
• monitor a downlink channel for initial system access information transmitted by an access node on the downlink channel, wherein the initial system information comprises an access allowed flag indicating whether the wireless terminal is allowed to transmit access requests for additional system access information to a cell served by the access node after acquiring synchronization;
• in response to the timer expiring before detection of the initial system access information, send an access request to the access node on an uplink channel to request additional system access information, wherein the access request indicates downlink resources on which the access node is to transmit the additional access system information;
• receive, responsive to the access request, the additional system access information from the access node on the downlink resources indicated in the access request.