Second level collision resolution for packet data communications

A code-division-multiple-access (CDMA) wireless base station, comprising:

• a CDMA transmitter;
• a CDMA receiver;
• and
• a controller coupled to the CDMA receiver for responding to signals received via the CDMA receiver and coupled for controlling the CDMA transmitter, such that in operation the CDMA base station is for performing the following steps:
• receiving at least a portion of an access burst from a remote station, the access burst comprising a sequence of coded preamble signals at sequentially increasing discrete power levels, each coded preamble signal in the sequence comprising one of a plurality of possible signature codes, the one signature code corresponding to one of a corresponding plurality of groups of common packet channels operated through the base station;
• detecting a first one of the coded preamble signals of the sequence that is received at an adequate power level;
• upon detection of the first coded preamble signal at the adequate power level, transmitting an access acknowledgement signal corresponding to the one signature code;
• receiving one of a plurality of collision detection preamble signals from the remote station;
• selecting an available one of the common packet channels of the one group;
• transmitting a collision detection acknowledgement signal corresponding to the received collision detection preamble signal and identifying the selected common packet channel;
• and
• receiving any of data and power control information over the selected common packet channel from the remote station.

A base-band processor, for use in a code-division-multiple-access (CDMA) wireless base station having a modulator and a demodulator, the base-band processor comprising:

• a preamble processor, coupled to the demodulator, for detecting a preamble in a received spread-spectrum signal;
• a data processor, coupled to the demodulator, for detecting and processing any data contained in the received spread-spectrum signal;
• an encoder, for encoding data;
• an interleaver, coupled to the encoder, for interleaving encoded data;
• a packet formatter, coupled to the interleaver, for formatting the interleaved data into a packet;
• and
• a controller coupled to the preamble processor and coupled for controlling the modulator, the data processor and the packet formatter, such that in operation the base-band processor is for performing the following steps:
• receiving at least a portion of an access burst from a remote station, the access burst comprising a sequence of coded preamble signals at sequentially increasing discrete power levels, each coded preamble signal in the sequence comprising one of a corresponding plurality of possible signature codes, the one signature code corresponding to one of a plurality of groups of the common packet channels operated through the base station;
• detecting a first one of the coded preamble signals of the sequence that is received at an adequate power level;
• upon detection of the first coded preamble signal at the adequate power level, transmitting an access acknowledgement signal corresponding to the one signature code
• receiving one of a plurality of collision detection preamble signals from the remote station;
• selecting an available one of the common packet channels of the one group;
• transmitting a collision detection acknowledgement signal corresponding to the received collision detection preamble signal and identifying the selected common packet channel;
• and
• receiving any of data and power control information over the selected common packet channel from the remote station.

A code-division-multiple-access (CDMA) wireless remote station, comprising:

• a CDMA transmitter;
• a CDMA receiver;
• and
• a controller coupled to the CDMA receiver for responding to signals received via the CDMA receiver and coupled for controlling the CDMA transmitter, such that in operation the CDMA remote station is for performing the following steps:
• selecting one of a plurality of groups of common packet channels from groups of common packet channels served through a base station;
• transmitting an access burst comprising a sequence of coded preamble signals at sequentially increasing discrete power levels, each coded preamble signal in the sequence comprising one of a plurality of possible signature codes, the one signature code corresponding to the selected group of common packet channels;
• receiving an acknowledgement signal corresponding to the one signature code from the base station;
• selecting one of a plurality of possible collision detection codes;
• transmitting the selected collision detection code;
• receiving a collision detection acknowledgement signal from the base station, the collision detection acknowledgement signal corresponding to the selected collision detection code and identifying one common packet channel from within the selected group;
• and
• transmitting any of data and control information over the one common packet channel following receipt of the collision detection acknowledgement signal.

A base-band processor, for use in a code-division-multiple-access (CDMA) wireless remote station having a spread-spectrum modulator and a spread-spectrum demodulator, the base-band processor, comprising:

• an acknowledgment detector, coupled to the demodulator, for detecting an acknowledgment in a received spread-spectrum signal;
• an encoder, for encoding data;
• an interleaver, coupled to the encoder, for interleaving encoded data;
• a preamble generator for generating a preamble;
• a multiplexer, coupled to the interleaver and to the preamble generator, for multiplexing the interleaved data and the preamble;
• a packet formatter, coupled to the multiplexer, for formatting the multiplexed data and preamble into one or more packets;
• and
• a controller coupled to the acknowledgment detector and coupled for controlling the modulator, the preamble generator, the multiplexer and the packet formatter, such that in operation the base-band processor is for performing the following steps:
• selecting one of a plurality of groups of common packet channels from groups of common packet channels served through a base station;
• transmitting an access burst comprising a sequence of coded preamble signals at sequentially increasing discrete power levels, each coded preamble signal in the sequence comprising one of a plurality of possible signature codes, the one signature code corresponding to the selected group of common packet channels;
• receiving an acknowledgement signal corresponding to the one signature code from the base station;
• selecting one of a plurality of possible collision detection codes;
• transmitting the selected collision detection code;
• receiving a collision detection acknowledgement signal from the base station, the collision detection acknowledgement signal corresponding to the selected collision detection code and identifying one common packet channel from within the selected group;
• and
• transmitting data over the one common packet channel following receipt of the collision detection acknowledgement signal.