Patent ID: 6842480
Filing Date: 2005-01-11
Classification: H04B

Abstract:
1. A programmable matched filter for processing a received spread-spectrum signal, to determine the likelihood that the received spread-spectrum signal was spread with a predetermined spreading code sequence, comprising: an integrator responsive to a chip stream of samples derived from the received spread-spectrum signal, for integrating a predetermined number of most recent samples from the chip stream to obtain an integration value; a plurality of control gates corresponding in number to the predetermined number of most recent samples, each of the control gates receiving a respective one of the samples at an input port and receiving a respective value of a reference code sequence comprising the predetermined spreading code sequence at a control port such that the control gate outputs a value of the respective sample if the received reference value bears a predetermined relationship to an identity value; at least one adder for summing the values output from the control gates to form a compensation value; and a circuit coupled to the at least one adder and to the integrator to modify the integration value by the compensation value.