Methods and apparatus for use in generating data sequences for spread spectrum communications

A method for use in generating one or more data sequences for spread spectrum communications, the method comprising:

• serially generating a Gold code sequence by, for each count value i of a plurality of count values:
• retrieving from memory a bit of a pseudorandom noise (PN) sequence corresponding to an (i+n)th position in the PN sequence, where n is a fixed integer value;
• retrieving from memory a bit of the PN sequence corresponding to an (q*i)th position in the PN sequence, where q is a fixed integer value;
• adding the bit corresponding to the (i+n)th position with the bit corresponding to the (q*i)th position;
• and
• wherein retrieving from memory a bit of the PN sequence corresponding to the (i+n)th position comprises applying an (i+n) value to the address inputs of the memory;
• and
• wherein retrieving from memory a bit of the PN sequence corresponding to the (q*i)th position comprises applying an (q*i) value to the address inputs of the memory.

A method for use in generating one or more data sequences for spread spectrum communications, the method comprising:

• serially generating a Gold code sequence by, for each count value i of a plurality of count values:
• retrieving from memory a bit of a pseudorandom noise (PN) sequence corresponding to an (i+n)th position in the PN sequence, where n is a fixed integer value;
• retrieving from memory a bit of the PN sequence corresponding to an (q*i)th position in the PN sequence, where q is a fixed integer value;
• adding the bit corresponding to the (i+n)th position with the bit corresponding to the (q*i)th position;
• and
• wherein the Gold code sequence is a first Gold code sequence, the method further comprising serially generating a second Gold code sequence by, for each count value i of the plurality of count values;
• retrieving from memory a bit of the PN sequence corresponding to the (i+n+m)th position in the PN sequence, where “m” is a fixed integer value;
• retrieving from memory a bit of the PN sequence corresponding to the (q*i+q*m)th position in the PN sequence;
• and
• adding the bit corresponding to the (i+n+m)th position with the bit corresponding to the (q*i+q*m)th position.

In a dual mode Code Division Multiple Access (CDMA), a method for generating an nth Gold code from a pseudorandom noise (PN) sequence stored sequentially in a memory as x(0), x(1), . . . , the method comprising the steps of:

• accessing the memory sequentially starting from location n in order to generate the sequence x(i+n), where n is a fixed integer value;
• accessing the memory non-sequentially starting from a first location (k) and then accessing each qth location in order to generate the sequence x(q*i+k) where q is a fixed integer value;
• and
• adding on a bit-by-bit basis the resulting two retrieved sequences x(i+n) and x(q*i+k).

A method of generating a complex Gold Code sequence, Z2n(i), where, x is a PN sequence stored sequentially as x(0), x(1), . . . , in a memory, the PN sequence having a length equal to 2M-1, the method comprising the steps of:

• accessing from the memory in sequences of x(i+n+m), x(q*i+q*m), x(i+n) and x(q*i);
• and
• performing the equation:
• Z2n(i)=x(i+n)+x(q*i)+j[x(i+n+m)+x(q*i+q*m) ]
• where, n and q are fixed integer values to produce the complex Gold Code sequence, and M, n and i are integer values.

A data sequence generator for serially generating one or more data sequences, the data sequence generator comprising:

• a memory;
• data stored in said memory;
• the data comprising a pseudo-random noise (PN) sequence;
• a counting device;
• a first adder, including:
• a first input coupled to an output of the counting device;
• a second input which receives a value n, wherein n is an integer value;
• a multiplier, including:
• a first input coupled to the output of the counting device;
• a second input which receives a value q, wherein q is an integer value;
• a first multiplexer, including:
• a first input coupled to an output of the first adder;
• a second input coupled to an output of the multiplier;
• and
• an output for coupling to memory address inputs of the memory.

A data sequence generator, comprising:

• a read-only memory (ROM) storing a pseudo-random noise (PN) sequence;
• a counter;
• a first adder, including:
• a first input coupled to the output of the counter;
• a second input which receives a value n, wherein n is an integer;
• a multiplier, including:
• a first input coupled to the output of the counter;
• a second input which receives a value q, wherein q is an integer;
• a first multiplexer, including:
• a first input coupled to an output of the first adder;
• a second input coupled to an output of the multiplier;
• a second multiplexer, including:
• a first input coupled to an output of the first multiplexer;
• a second input coupled to the output of the counter;
• and
• an output of the second multiplexer coupled to an address input of the ROM.

A data sequence generator for use in direct sequence spread spectrum (DSSS) communications, comprising:

• memory;
• a pseudo-random noise (PN) sequence stored in the memory;
• a counter for use in generating each count value i of a plurality of count values;
• an output of the memory to provide, for each count value i received at memory address inputs, a bit of the PN sequence corresponding to the (i)th position in the PN sequence, where n is a fixed integer value;
• an output of the memory to provide, for each (i+n) value received at the memory address inputs, a bit of the PN sequence corresponding to the (i+n)th position in the PN sequence, where q is a fixed integer value;
• an output of the memory to provide, for each (q*i) value received at the memory address inputs, a bit of the PN sequence corresponding to the (q*i)th position in the PN sequence;
• and
• an adder to provide a sum of the bit corresponding to the (i+n)th position and the bit corresponding to the (q*i)th position, to thereby provide a Gold code sequence.