Method employed by a base station for controlling initial power ramp-up using short codes

• US 20050254478A1
• Filed: 06/29/2005
• Published: 11/17/2005
• Est. Priority Date: 06/27/1996
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Lomp, Gary R., Ozluturk, Fatih M.
• Granted Patent: US 7,286,847 B2
• Time in Patent Office: Days
• US Class Current: 370/342
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04B 1/7075 with code phase acquisition
• CPC Class Codes: H04B 1/70753 Partial phase search
• CPC Class Codes: H04B 1/70755 Setting of lock conditions, e.g. threshold
• CPC Class Codes: H04B 1/70758 Multimode search, i.e. using multiple search strategies
• CPC Class Codes: H04B 1/7077 Multi-step acquisition, e.g. multi-dwell, coarse-fine or validation
• CPC Class Codes: H04B 1/708 Parallel implementation
• CPC Class Codes: H04B 2201/70701 featuring pilot assisted reception
• CPC Class Codes: H04B 2201/70702 Intercell-related aspects
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates
• CPC Class Codes: H04B 2201/7071 with dynamic control of receiver resources
• CPC Class Codes: H04B 7/2628 using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA] H04B7/2618 takes precedence
• CPC Class Codes: H04W 52/36 with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 52/60 using different transmission rates for TPC commands

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.

Claims

1. A method for a code division multiple access (CDMA) base station, the method comprising:

detecting a portion of a first code, the detected portion carrying no data;

transmitting an acknowledgement upon detection of the first code; and

receiving a remainder of the first code of the detected portion after transmission of the acknowledgement.

2. A code division multiple access base station comprising:

means for detecting a portion of a first code, the detected portion carrying no data;

means for transmitting an acknowledgement upon detection of the first code; and

means for receiving a remainder of the first code of the detected portion after transmission of the acknowledgement.

3. A code division multiple access base station comprising:

a code detector for detecting a portion of a first code, the detected portion carrying no data;

a transmitter for transmitting an acknowledgement upon detection of the first code; and

a receiver for receiving a remainder of the first code of the detected portion after transmission of the acknowledgement.