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US 8,009,636 B2Granted
Method and apparatus for performing an access procedure
AssigneeInterDigital Technology Corporation
InventorsFatih Ozluturk, Gary R. Lomp
Life of this patent
Estimating the term…
Abstract
A base station for controlling transmission power during the establishment of a communication channel utilizes the reception of a short code during initial power ramp-up. The short code is a sequence for detection by the base station which has a much shorter period than a conventional access code. The ramp-up starts from a power level that is lower than the required power level for detection by the base station. The power of the short code is quickly increased until the signal is detected by the base station. Once the base station detects the short code, it transmits an indication that the short code has been detected.
Claims39
A wireless code division multiple access (CDMA) subscriber unit comprising:
- a transmitter configured such that, when the subscriber unit is first accessing a CDMA network, the transmitter successively sends transmissions wherein each of the transmissions are derived from a first length of a plurality of chips until the subscriber unit receives from a base station associated with the network an indication that at least one of the transmissions has been detected by the base station;
- and
- the transmitter further configured such that, subsequent to the subscriber unit receiving the indication, the transmitter sends a subsequent transmission derived from a second length of the plurality of chips, wherein the first length is less than the second length.
A communication method for use with a code division multiple access (CDMA) subscriber unit, the method comprising:
- producing, based on a series of chips, a first portion of the series of chips, and
- a second portion of the series of chips, the first portion having a first length and the second portion having a second length which is greater than the first length;
- sending a first radio frequency (RF) transmission from an antenna of the CDMA subscriber unit, the first (RF) transmission including chips that are derived from the first portion;
- in an absence of an acknowledgement signal received by the CDMA subscriber unit, sending a second RF transmission from an antenna of the subscriber unit, wherein the second RF transmission includes chips derived from the first portion:
- and
- in response to an acknowledgement received by the CDMA subscriber unit, a third RF transmission is sent, the third RF transmission is derived from the second portion.
3 more elements
A code division multiple access (CDMA) subscriber unit, comprising:
- a circuit configured to produce, based on a series of chips, a first portion of the series of chips and a second portion of the series of chips, the first portion having a first length and the second portion having a second length greater than the first length;
- and
- an antenna coupled to the circuit, wherein the circuit is configured to send from the antenna a first radio frequency (RF) transmission including chips derived from the first portion,
- wherein in an absence of an acknowledgement received by the CDMA subscriber unit, the circuit is configured to send a second RF transmission from the antenna wherein the second RF transmission includes chips derived from the first portion;
- and
- in response to an acknowledgement received by the CDMA subscriber unit, a third RF transmission is sent, the third RF transmission is derived from the second.
3 more elements
A wireless subscriber unit comprising:
- a transmitter configured to send a plurality of transmissions to a base station of a wireless network as part of an access procedure, wherein a first transmission of the plurality of transmissions includes a first plurality of transmitted chips, and a second transmission of the plurality of transmissions includes a second plurality of transmitted chips that are different from the first plurality of transmitted chips;
- a receiver configured to receive an indication that a base station has received at least one of the plurality of transmissions;
- and
- wherein the transmitter is further configured to send, in response to the receiver receiving the indication, a subsequent transmission including a third plurality of transmitted chips;
- wherein each of the first and second plurality of transmitted chips is shorter than the third plurality of transmitted chips.
2 more elements
A wireless code division multiple access (CDMA) subscriber unit comprising:
- a transmitter configured such that, when the subscriber unit is accessing a CDMA network, the transmitter successively sends transmissions having a first plurality of chips until the subscriber unit receives an indication from a base station that the base station has detected at least one of the transmissions;
- the transmitter further configured such that, subsequent to the subscriber unit receiving the indication, the transmitter sends a transmission having a second plurality of chips;
- wherein the first plurality of chips and the second plurality of chips are derived from a third plurality of chips;
- and
- wherein the first plurality of chips has fewer chips than the second plurality of chips.
2 more elements
A subscriber unit for use in a code division multiple access (CDMA) network, comprising:
- a processor configured to produce first chip sequences for use in deriving respective first transmissions, each first transmission having a same first length;
- wherein the first chip sequences are not used for spreading when deriving the first transmissions and wherein at least two of the first chip sequences are different;
- a transmitter configured to send the first transmissions to a base station of the CDMA network one after another;
- and
- a receiver configured to receive an acknowledgement sent from the base station of the CDMA network to the subscriber unit, wherein the acknowledgement indicates that at least one of the first transmissions has been detected by the base station;
- the processor further configured to produce a second chip sequence for use in deriving a second transmission having a second length greater than the same first length;
- wherein the first chip sequences and the second chip sequence are derived from a third chip sequence;
- the transmitter further configured to send the second transmission to the base station subsequent to the receiver receiving the acknowledgement.
5 more elements
Dependencies are inferred from the claim text.