Transmission of system information on a downlink shared channel

Abstract

In one embodiment, a method of transmitting system information on a downlink shared channel structured as successive subframes includes transmitting system information in regularly occurring time windows, each time window spanning some number of successive subframes. The method further includes indicating to receiving user equipment which subframes within a given time window carry system information. The method and variations of it are applied, for example, to the transmission of dynamic system information on the downlink shared channel or other downlink channel in a 3GPP E-UTRA wireless communication network.

What is claimed is: 
     
       1. A method of transmitting system information on a downlink shared channel of a wireless communication network, the method comprising:
 transmitting system information on the downlink shared channel in recurring time windows, each of the time window windows spanning one or more subframes, 
 wherein a set of subframes out of the one or more subframes within a time window is used for carrying the system information; and 
 setting an indicator in each subframe in the set of subframes that is used for carrying the system information to indicate to receiving user equipment that the subframe carries system information 
 in each subframe from said set of subframes that is used for carrying the system information, using an indicator to indicate to receiving user equipment that the subframe carries system information, wherein the indicator is a Radio Network Temporary Identifier (RNTI). 
 
     
     
       2. The method of  claim 1 , wherein the indicator is a System Information Radio Network Temporary Identifier (SI-RNTI). 
     
     
       3. The method of  claim 1 , wherein the set of subframes within the time window is a contiguous set of subframes within the time window. 
     
     
       4. The method of  claim 1 , wherein the set of subframes within the time window is a non-contiguous set of subframes within the time window. 
     
     
       5. The method of  claim 1 , wherein the set of subframes within the time window used for carrying the system information is dynamically selected in view of competing transmission priorities associated with other control or data signaling. 
     
     
       6. The method of  claim 1 , wherein using an indicator in each subframe in the set of subframes that is used for carrying the system information to indicate to receiving user equipment that the subframe carries system information includes further comprising using an end-of-system-information indicator in a last subframe of the time window that carries system information. 
     
     
       7. The method of  claim 1 , further comprising varying window sizes of the recurring time windows. 
     
     
       8. The method of  claim 1 , further comprising dynamically configuring a window size for the recurring time windows. 
     
     
       9. The method of  claim 1 , wherein using an indicator in each subframe in the set of subframes that is used for carrying the system information to indicate to receiving user equipment that the subframe carries system information includes using different indicators corresponding to different types of system information, such that the indicator used for a particular subframe indicates the type of system information carried in that subframe. 
     
     
       10. A network transmitter comprising a baseband processor configured to:
 generate system information for transmission on a downlink shared channel in recurring time windows, each of the time window windows spanning one or more subframes, wherein a set of subframes out of the one or more subframes within a time window is used for carrying the system information; and 
 set an indicator in each subframe in the set of subframes that is used for carrying the system information to indicate to receiving user equipment that the subframe carries system information 
 in each subframe from the set of subframes that is used for carrying the system information, use an indicator to indicate to receiving user equipment that the subframe carries system information, wherein the indicator is a Radio Network Temporary Identifier (RNTI). 
 
     
     
       11. The network transmitter of  claim 10 , wherein the network transmitter comprises a radio base station configured for operation in accordance with 3GPP E-UTRA standards. 
     
     
       12. A method for a user equipment to receive system information from a supporting wireless communication network, the method comprising:
 monitoring, by the user equipment, at least one subframe within a time window for an indication of presence of system information in the at least one subframe, the time window being one of a set of recurring time windows used for transmission of the system information, each of said recurring time windows spanning a number of subframes, and wherein, in the recurring time windows, said indication being is present in each subframe where system information is present; 
 and reading, by the user equipment, system information from the at least one subframe when said indication is present in the at least one subframe, wherein the indication is a Radio Network Temporary Identifier (RNTI). 
 
     
     
       13. The method of  claim 12 , wherein the indication is a System Information Radio Network Temporary Identifier (SI-RNTI). 
     
     
       14. The method of  claim 12 , further comprising recognizing an end-of-system-information indicator in a subframe received within the time window and terminating monitoring within the time window in response. 
     
     
       15. The method of  claim 12 , further comprising adapting to changing or configurable window sizes used for the time window. 
     
     
       16. The method of  claim 12 , further comprising storing a default window size for monitoring for system information transmissions. 
     
     
       17. The method of  claim 12 , further comprising monitoring for system information transmissions based on a specified window size indicated in received information rather than the default window size. 
     
     
       18. The method of  claim 12 , further comprising recognizing different types of system information based on recognizing different system information indicators in different subframes. 
     
     
       19. The method of  claim 12 , wherein the method comprises the user equipment receiving the system information transmitted in recurring time windows from a supporting wireless communication network. 
     
     
       20. The method of  claim 19 , wherein the wireless communication network is an Orthogonal Frequency Division Multiplexing (OFDM) based wireless communication network. 
     
     
       21. The method of  claim 1 , wherein, for time windows from among the recurring time windows, there are frames in between consecutive time windows.  
     
     
       22. The method of  claim 1 , further comprising:
 selecting the set of subframes from among the one or more subframes within a time window.    
     
     
       23. The method of  claim 1 , further comprising:
 generating one or more scheduling units including the system information, wherein the scheduling units are transmitted in the recurring time windows.    
     
     
       24. The method of  claim 1 , further comprising:
 informing a user equipment via system information about a window size of the recurring time windows.    
     
     
       25. The network transmitter of  claim 10 , wherein the baseband processor is configured to use an end-of-system-information indicator in a last subframe of the time window that carries system information.  
     
     
       26. The network transmitter of  claim 10 , wherein, for time windows from among the recurring time windows, there are frames in between consecutive time windows.  
     
     
       27. The network transmitter of  claim 10 , wherein the baseband processor is further configured to:
 select the set of subframes from among the one or more subframes within a time window.    
     
     
       28. The network transmitter of  claim 10 , wherein the baseband processor is further configured to:
 generate one or more scheduling units including the system information, wherein the scheduling units are transmitted in the recurring time windows.    
     
     
       29. The network transmitter of  claim 10 , wherein the baseband processor is further configured to:
 inform a user equipment via system information about a window size of the recurring time windows.    
     
     
       30. The method of  claim 12 , wherein, for time windows from among the recurring time windows, there are frames in between consecutive time windows.  
     
     
       31. The method of  claim 12 , wherein the user equipment receives the system information in one or more scheduling units transmitted by the wireless communication network in the recurring time windows.  
     
     
       32. The method of  claim 12 , further comprising:
 being informed via system information about a window size of the recurring time windows, wherein the monitoring is performed based on the window size.    
     
     
       33. A user equipment comprising a baseband processor configured to:
 monitor at least one subframe within a time window for an indication of presence of system information in the at least one subframe, the time window being one of a set of recurring time windows used for transmission of the system information, each of said recurring time windows spanning a number of subframes, wherein, in the recurring time windows, the indication is present in each subframe where system information is present; and   read system information from the at least one subframe when said indication is present in the at least one subframe, wherein the indication is a Radio Network Temporary Identifier (RNTI).    
     
     
       34. The user equipment of  claim 33 , wherein the baseband processor is further configured to:
 recognize an end-of-system-information indicator in a subframe received within the time window and terminate monitoring within the time window in response.    
     
     
       35. The user equipment of  claim 33 , wherein, for time windows from among the recurring time windows, there are frames in between consecutive time windows.  
     
     
       36. The user equipment of  claim 33 , wherein the baseband processor is configured to receive the system information in one or more scheduling units transmitted by the wireless communication network in the recurring time windows.  
     
     
       37. The user equipment of  claim 33 , wherein the baseband processor is further configured to:
 be informed via system information about a window size of the recurring time windows, wherein the monitoring is performed based on the window size.