초록 ▼

An efficient, multichannel filter for CDMA modems permits multiple serial, digital bit streams to be filtered by digital signal processing techniques including sample weighting and summing functions. Each individual channel may have custom weighting coefficients or weighting coefficients common for

An efficient, multichannel filter for CDMA modems permits multiple serial, digital bit streams to be filtered by digital signal processing techniques including sample weighting and summing functions. Each individual channel may have custom weighting coefficients or weighting coefficients common for all channels. If the weighting coefficients are by adapation, the same approach may be taken. The multichannel FIR filter is implemented with no multipliers and a reduction in the number of adders. To increase the speed of operation, the filter structure utilizes look-up tables storing the weighting coefficients. The invention can be embodied as either as a field programmable gate array or an application specific integrated circuit. The use of look-up tables saves significant chip resources.

대표청구항 ▼

1. A multichannel, digital filter for code division multiple access telecommunication systems comprising:a plurality of filter inputs, each input comprising a channel; a filter output; first and second memories, each memory coupled to said plurality of filter inputs and each memory having an output;

1. A multichannel, digital filter for code division multiple access telecommunication systems comprising:a plurality of filter inputs, each input comprising a channel; a filter output; first and second memories, each memory coupled to said plurality of filter inputs and each memory having an output; a first storage register having an input coupled to the output of said first memory and having an output; a first summer having a first input coupled to said first storage register and a second input coupled to the output of said second memory, said first summer having an output; and a second storage register coupled to said output of said first summer and having an output; wherein said output of said second storage register comprises said filter output.