Radio resource allocation for cellular wireless networks
View Patent ↗Embodiments of the invention relate to cellular wireless networks and are particularly suited to networks including different types of base stations. So-called femtocell types of base stations are typically deployed within a subscriber's premises and operate at low transmit power, providing a very limited area of wireless coverage. A femtocell is typically deployed within the area of wireless coverage of a conventional macrocell, occupying the same frequency spectrum and timeslots as the macrocell. A problem can be presented to a user equipment terminal that is close to the femtocell but unable to gain access to it, because the transmissions from the femtocell may appear as interference to the user equipment terminal, preventing it from accessing the macrocell which it could otherwise access. A cellular wireless network according to an embodiment of the invention employs a method of allocating radio resource to femtocells so that the transmissions from femtocells do not occupy the same radio resource blocks as those used by the macrocell for signalling; embodiments of the invention thereby prevent interference associated with signalling to cause a connection to be lost, or prevent a connection being set up.
1. A method of allocating radio resources in a radio communications network, the radio communications network comprising a first base station open for access to substantially any user equipment terminal of the radio communications network and a second base station open for access to only a predetermined one or more user equipment terminals of the radio communications network, wherein the first base station is arranged to use a first plurality of radio resource blocks for radio communications with user equipment terminals, and the first plurality includes one or more radio resource blocks useable by the first base station for signalling, the method comprising:
allocating a second plurality of radio resource blocks for use by the second base station in radio communications with user equipment terminals,
wherein the first plurality and the second plurality of radio resource blocks have at least one radio resource block in common, and wherein the second plurality of radio resource blocks does not include said one or more radio resource blocks useable by the first base station for signalling.
2. A method according to claim 1 , wherein each respective radio resource block is associated with a different frequency.
3. A method according to claim 2 , wherein the first plurality of radio resource blocks occupies a contiguous frequency range.
4. A method according to claim 2 , wherein the second plurality of radio resource blocks occupies a contiguous frequency range.
5. A method according to claim 1 , wherein the second plurality of radio resource blocks is a subset of the first plurality of radio resource blocks.
6. A method according to claim 1 , wherein the one or more of said radio resource blocks useable by the first base station for signalling include radio channels for synchronization, broadcast and for transmitting control signalling.
7. A method according to claim 1 , wherein the radio communications network comprises a further base station open for access to only a predetermined one or more user equipment terminals, the method further comprising allocating a further plurality of radio resource blocks for use by the further base station for radio communications with user equipment terminals, wherein the first and further pluralities of radio resources share at least one radio resource block,
wherein the further plurality of radio resources excludes said one or more of said radio resource blocks useable by the first base station for signalling, and wherein the second plurality of radio resource blocks and the further plurality of radio resource blocks includes one or more radio resource blocks different than those useable by the second and further base stations respectively for signalling.
8. A node of a radio communication network arranged to allocate radio resources in a radio communication network, the radio communications network comprising a first base station open for access to substantially any user equipment terminal supported by the radio communications network and a second base station open for access to only a predetermined one or more user equipment terminals of the radio communications network, wherein the first base station is arranged to use a first plurality of radio resource blocks for radio communications with user equipment terminals, and the first plurality includes one or more radio resource blocks useable by the first base station for signalling, the node being arranged to:
allocate a second plurality of radio resource blocks for use by the second base station in radio communications with said predetermined one or more user equipment terminals,
wherein the first plurality and second plurality of radio resources blocks have at least one radio resource block in common, and wherein the second plurality of radio resources blocks does not contain said one or more of said radio resource blocks useable by the further base station for signalling.
9. A base station of a radio communications network, the base station being open for access to substantially any user equipment terminal of the radio communications network, the radio communications network further comprising a further base station, arranged to be open for access to only a predetermined one or more user equipment terminals, said base station being arranged to use a first plurality of radio resource blocks for radio communications with user equipment terminals, the first plurality of radio resource blocks including one or more radio resource blocks useable by said base station for signalling, said base station being arranged to:
allocate a second plurality of radio resource blocks for use by the further base station for radio communications with said predetermined one or more user equipment terminals,
wherein the first plurality and second plurality of radio resource blocks share at least one radio resource block, and wherein the second plurality of radio resource blocks does not contain said one or more of said radio resource blocks useable by said base station for signalling.
10. A base station of a radio communications network, the base station being arranged to be open for access to only a predetermined one or more user equipment terminals, the radio communications network further comprising a further base station arranged to be open for access to substantially any user equipment terminal of the radio communications network, and being arranged to use a first plurality of radio resource blocks for radio communications with user equipment terminals, the first plurality of radio resource blocks including one or more radio resource blocks useable by the further base station for signalling, wherein said base station is arranged to:
allocate a second plurality of radio resource blocks for use by said base station for radio communications with said predetermined one or more user equipment terminals,
wherein the first plurality and second plurality of radio resource blocks share at least one radio resource block, and wherein the second plurality of radio resource blocks does not contain said one or more of said radio resource blocks useable by the further base station for signalling.