Method of and apparatus for activating a spread-spectrum radiotelephone

A method of activating a radiotelephone operating in a slotted paging mode, the radiotelephone operable in a code division multiple access (CDMA) radiotelephone system, the method comprising, in combination:

• activating a searcher receiver;
• detecting a pilot signal;
• acquiring a PN sequence timing related to a PN sequence associated with the pilot signal;
• activating at least one demodulation branch after activating the searcher receiver;
• synchronizing the at least one demodulation branch to the searcher receiver;
• activating a system timing unit after activating the searcher receiver;
• and
• synchronizing the system timing unit relative to the at least one demodulation branch after synchronizing the at least one demodulation branch.

An apparatus for operating a code division multiple access (CDMA) radiotelephone in a slotted paging mode, the apparatus comprising:

• a searcher receiver periodically activated to find a pilot signal of suitable signal strength, the searcher receiver acquiring a pseudorandom noise (PN) sequence timing of the pilot signal after each periodic activation of the searcher receiver;
• at least one demodulation branch coupled to the searcher receiver;
• control circuitry to periodically activate the at least one demodulation branch after each periodic activation of the searcher receiver and to direct the at least one demodulation branch to synchronize relative to the searcher receiver after each periodic acquiring of the PN sequence timing;
• and
• a system timing unit coupled to the at least one demodulation branch, the control circuitry periodically activating the system timing unit substantially after each periodic activation of the searcher receiver, the control circuitry directing the system timing unit to synchronize relative to the PN sequence timing of the pilot signal after each periodic synchronization of the at least one demodulation branch.

A method of activating a code division multiple access (CDMA) radiotelephone operating in a slotted paging mode of a CDMA cellular telephone system, the method comprising the steps of:

• activating a searcher receiver;
• acquiring, with the searcher receiver, a pseudo-random noise (PN) sequence timing of a PN sequence associated with a pilot signal;
• activating at least one demodulation branch after activating the searcher receiver, wherein the at least one demodulation branch is activated after acquiring the PN sequence timing of the pilot signal;
• slewing a PN timing of the searcher receiver to the PN sequence timing of the pilot signal;
• and
• synchronizing the at least one demodulation branch to the PN timing of the searcher receiver after slewing the PN timing of the searcher receiver, wherein synchronizing the at least one demodulation branch comprises parallel loading PN state information from the searcher receiver into the at least one demodulation branch.

A method of activating a code division multiple access (CDMA) radiotelephone operating in a slotted paging mode of a CDMA cellular telephone system, the method comprising the steps of:

• activating a searcher receiver;
• acquiring, with the searcher receiver, a pseudo-random noise (PN) sequence timing of a PN sequence associated with a pilot signal;
• activating at least one demodulation branch after activating the searcher receiver, wherein the at least one demodulation branch is activated after acquiring the PN sequence timing of the pilot signal;
• slewing a PN timing of the searcher receiver to the PN sequence timing of the pilot signal;
• synchronizing the at least one demodulation branch to the PN timing of the searcher receiver after slewing the PN timing of the searcher receiver;
• activating a system timing unit after activation of the searcher receiver;
• and
• synchronizing the system timing unit to the at least one demodulation branch after slewing the PN timing of the searcher receiver.

A method of activating a radiotelephone during slotted paging mode operation, the radiotelephone operable in a code division multiple access radiotelephone system, the method comprising, in combination:

• activating a searcher receiver;
• detecting a pilot signal that produces a correlation energy above a predetermined threshold;
• acquiring a PN sequence timing of the pilot signal with the searcher receiver;
• activating a system timing unit after acquiring the PN sequence timing of the pilot signal;
• activating at least one demodulation branch after acquiring the PN sequence timing of the pilot signal;
• synchronizing the at least one demodulation branch to the PN sequence timing of the pilot signal after acquiring the PN sequence timing;
• and
• synchronizing the system timing unit to the PN sequence timing of the pilot signal after synchronizing the at least one demodulation branch.

A method of activating a radiotelephone in a slotted paging mode, the radiotelephone operable in a code division multiple access (CDMA) radiotelephone system, the method comprising the steps of:

• programming a pseudorandom noise (PN) sequence awake state;
• activating at least a portion of a searcher receiver;
• loading the PN sequence awake state;
• incrementing at a first rate the PN sequence awake state to generate a local PN sequence;
• detecting at least one pilot signal having an associated PN sequence;
• storing digital samples of the at least one pilot signal at the first rate;
• searching at a second rate for a pilot signal and an associated PN sequence phase that produces a correlation energy above a predetermined threshold, the second rate faster than the first rate;
• slewing the local PN sequence to the PN sequence phase associated with the pilot signal;
• activating a system timing unit after the step of slewing;
• activating at least one demodulation branch after the step of slewing;
• synchronizing a PN timing of the at least one demodulation branch to the PN sequence phase associated with the pilot signal after the step of slewing;
• and
• synchronizing a PN timing of the system timing unit to the PN sequence phase associated with the pilot signal after the step of synchronizing the PN timing of the at least one demodulation branch.