Methods and apparatus for measuring control carrier signal strength in wireless communications systems employing discontinuous control carrier transmissions

Claim 2

A base station site synchronized cellular communications system, wherein downlink control channel transmission are allocated on discontinuous control channel carrier, comprising: a first base station; a second, neighboring base station; and a mobile station being served by the first base station, the mobile station including a measurement unit adapted to make measurements of control channel signaling of the neighboring base station, wherein the measurement unit: identifies a time slot during which the neighboring base station transmits control channel signaling, defines a duration of a control channel signaling measurement window to be less than a duration of the identified timeslot, aligns the control channel signaling measurement window such that the measurements of the control channel signaling from the neighboring base station actually arrives at the measurement unit of the mobile station, and adjusts the position of the measurement window based on a determination of an absolute time reference from the first base station.

Claim 3

The system of claim 1 , wherein the serving base station transmits information regarding the relative geographic positions of the serving and neighboring base stations to the mobile station, and wherein the measurement unit adjusts the position of the measurement window based on the transmitted information.

Claim 4

The system of claim 1 , wherein the measurement unit determines a difference between a propagation delay from the serving base station and a propagation delay from the neighboring base station, and adjusts the position of the measurement window based on the determined difference.

Claim 5

The system of claim 3 , wherein the mobile station determines the difference between propagation delays by reading a synchronization burst transmittal by the neighboring base station.

Claim 6

The system of claim 1 , wherein the measurement unit determines a position of a timeslot of the serving base station which corresponds with the identified timeslot of the neighboring base station, and positions the measurement window late in the timeslot of the serving base station.

Claim 7

In a base station site synchronized cellular communications system, wherein downlink control channel transmissions are allocated on discontinuous control channel carriers, and wherein a mobile station is served by a first base station, a method for enabling the mobile station to make signal strength measurements on control channel transmissions from a second, neighboring base station, comprising the steps of: identifying a time slot during which the neighboring base station transmits control channel signaling; defining a duration of a measurement window in which a measuring unit of the mobile station makes measurements of the neighboring base station control channel signaling, the duration of the measurement window being less than a duration of the identified timeslot; and aligning the measurement window such that the measurements are made when the control channel signaling from the neighboring base station actually arrives at the measuring unit of the mobile station, wherein the position of the measurement window is adjusted based on a determination of an absolute time reference from the first base station.

Claim 8

In a base station site synchronized cellular communications system, wherein downlink control channel transmissions are allocated on discontinuous control channel carriers, and wherein a mobile station is served by a first base station, a method for enabling the mobile station to make signal strength measurements on control channel transmissions from a second, neighboring base station, comprising the steps of: identifying a time slot during which the neighboring base station transmits control channel signaling; defining a duration of a measurement window in which a measuring unit of the mobile station makes measurements of the neighboring base station control channel signaling, the duration of the measurement window being less than a duration of the identified timeslot; and aligning the measurement window such that the measurements are made when the control channel signaling from the neighboring base station actually arrives at the measuring unit of the mobile station, wherein the position of the measurement window is adjusted based on a determination of an absolute time reference from the first base station.

Claim 9

The method of claim 6 , wherein the step of aligning the measurement window includes the steps of: transmitting information regarding the relative geographic positions of the serving and neighboring base stations from the serving base station to the mobile station; and adjusting the position of the measurement window based on the transmitted information.

Claim 10

The method of claim 6 , wherein the step of aligning the measurement window includes the steps of: determining a difference between a propagation delay from the serving base station and a propagation delay from the neighboring base station; and adjusting the position of the measurement window based on the determined difference.

Claim 11

The method of claim 8 , wherein the mobile station determines the difference between propagation delays by reading a synchronization burst transmitted by the neighboring base station.

Claim 12

The method of claim 6 , wherein the step of aligning the measurement window includes the steps of: determining the position of a timeslot of the serving base station which corresponds with the identified timeslot of the neighboring base station; and positioning the measurement window late in the timeslot of the serving base station.