1. A frequency-division multiplexing system for use with M greater than or equal to two transmit antennas and N greater than or equal to two receive antennas, comprising:
(a) a mapper modulator configured to map each of a plurality of incoming sets of message bits to a current M\xd7M unitary symbol matrix;
(b) a differential modulator configured to generate, in a sequence of repetitions, a sequence of consecutive differential M\xd7M unitary space-frequency signal matrices by performing in each new repetition a differential action between said differential M\xd7M unitary space-frequency signal matrix resulting from a last repetition and said current M\xd7M unitary symbol matrix, thereby to generate a new differential M\xd7M unitary space-frequency signal matrix,
wherein said differential action is carried out such that said message bits mapped to said current M\xd7M unitary symbol matrix are encoded as a differential between two consecutive differential M\xd7M unitary space-frequency signal matrices,
wherein said differential is substantially invariant to frequency-response conditions in a propagation channel between said transmit and receive antennas; and
(c) a time-frequency transformer configured to accept each differential M\xd7M unitary space-frequency signal matrix as a signal distributed over antennas and frequency sub-channels such that consecutive differential M\xd7M unitary space-frequency signal matrices are distributed over consecutive frequency sub-channels, and
further configured to transform each differential M\xd7M unitary space-frequency signal matrix to a corresponding space-time transmit signal distributed over two or more antennas and time for transmission over a given time window.
2. The system as recited in claim 1 wherein said differential modulator is a differential OFDM modulator.
3. The system as recited in claim 1 wherein said mapper modulator comprises a Cayley mapper modulator.
4. The system as recited in claim 1 wherein said time-frequency transformer applies an Inverse Fast Fourier Transform to said differential M\xd7M unitary space-frequency signal matrices.
5. The system as recited in claim 1 wherein said space-time transmit signals include a guard interval.
6. The system as recited in claim 1 wherein said differential modulator is configured to generate a transformation of said differential M\xd7M unitary space-frequency signal matrix within a single OFDM symbol interval.
7. A frequency-division multiplexing method for use with M greater than or equal to two transmit antennas and N greater than or equal to two receive antennas, comprising:
mapping each of a plurality of incoming sets of message bits to a current M\xd7M unitary symbol matrix;
generating, in a sequence of repetitions, a sequence of differential M\xd7M unitary space-frequency signal matrices by performing in each new repetition a differential action between said differential M\xd7M unitary space-frequency signal matrix resulting from a last said repetition and said current M\xd7M unitary symbol matrix, thereby to generate a new differential M\xd7M space-frequency signal matrix;
wherein said differential action is carried out such that said message bits mapped to said current M\xd7M symbol matrix are encoded as a differential between two consecutive differential M\xd7M unitary space-frequency signal matrices,
wherein said differential is substantially invariant to frequency-response conditions in a propagation channel between said transmit and receive antennas,
providing each differential M\xd7M unitary space-frequency signal matrix as a signal distributed over antennas and frequency sub-channels such that consecutive differential M\xd7M unitary space-frequency signal matrices are distributed over consecutive frequency sub-channels; and
transforming each differential M\xd7M unitary space-frequency signal matrix to a corresponding space-time transmit signal distributed over antennas and time for transmission over a given time window.
8. The method as recited in claim 7 wherein said generating is carried out by a differential OFDM modulator.
9. The method as recited in claim 7 wherein said mapping is carried out by a Cayley mapper modulator.
10. The method as recited in claim 7 wherein said transforming of signal matrices to space-time transmit signals comprises applying an Inverse Fast Fourier Transform to said differential M\xd7M unitary space-frequency signal matrices.
11. The method as recited in claim 7 wherein said space-time transmit signals include a guard interval.
12. The method as recited in claim 7 wherein said method is carried out so as to provide and transform each differential M\xd7M unitary space-frequency signal matrix within a single OFDM symbol interval.
13. A frequency-division demultiplexing system for use with M greater than or equal to two transmit antennas and N greater than or equal to two receive antennas, comprising:
(a) a time-frequency transformer that transforms space-time receive signals from said N receive antennas into differential M\xd7M unitary space-frequency signal matrices, wherein each said space-frequency signal is distributed over antennas and frequency sub-channels such that consecutive differential M\xd7M unitary signal matrices are distributed over consecutive frequency sub-channels;
(b) a differential demodulator operative to generate from an input sequence of differential M\xd7M unitary space-frequency signal matrices, in a sequence of repetitions, a sequence of consecutive M\xd7M unitary symbol matrices, by performing in each new repetition a differential demodulation between a prior received differential M\xd7M unitary signal matrix and a current received differential M\xd7M unitary signal matrix, thereby recovering a current M\xd7M unitary symbol matrix, wherein the recovery of said current M\xd7M unitary symbol matrix is substantially invariant to frequency-response conditions in a propagation channel between said transmit and receive antennas; and
(c) a mapper demodulator configured to map each said current M\xd7M unitary symbol matrix to an outgoing set of message bits.
14. The system as recited in claim 13 wherein said differential demodulator is a differential OFDM demodulator.
15. The system as recited in claim 13 wherein said mapper demodulator comprises an inverse Cayley mapper.
16. The system as recited in claim 13 wherein said time-frequency transformer applies a Fast Fourier Transform to said space-time receive signals.
17. The system as recited in claim 13 wherein said space-time receive signals include a guard interval.
18. The system as recited in claim 13 wherein each said M\xd7M unitary space-frequency symbol matrix is recovered within a single OFDM symbol interval.
19. A frequency-division demultiplexing method for use with M greater than or equal to two transmit antennas and N greater than or equal to two receive antennas, comprising:
transforming space-time receive signals from said N receive antennas into differential M\xd7M unitary space-frequency signal matrices, wherein each said differential M\xd7M space-frequency signal matrix signal is distributed over antennas and frequency sub-channels such that consecutive differential M\xd7M unitary signal matrices are distributed over consecutive frequency sub-channels;
generating, from a differential demodulation of an input sequence of differential M\xd7M unitary space-frequency signal matrices, in a sequence of repetitions, a sequence of consecutive M\xd7M unitary symbol matrices, by performing in each new repetition a differential demodulation between a prior received differential M\xd7M unitary signal matrix and a current received differential M\xd7M unitary signal matrix, thereby recovering an M\xd7M unitary symbol matrix,
wherein the recovery of received M\xd7M unitary symbol matrices is substantially invariant to frequency-response conditions in a propagation channel between said transmit and receive antennas; and
demodulating each said current M\xd7M unitary symbol matrix to a set of message bits.
20. The method as recited in claim 19 wherein said transforming is carried out by a differential OFDM demodulator.
21. The method as recited in claim 19 wherein said demodulating is carried out by an inverse Cayley mapper demodulator.
22. The method as recited in claim 19 wherein said transforming comprises applying a Fast Fourier Transform to said space-time receive signals.
23. The method as recited in claim 19 wherein said space-time receive signals include a guard interval.
24. The method as recited in claim 19 wherein the recovery of each symbol matrix is carried out within a single OFDM symbol interval.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A computer-implemented method comprising:
receiving a user selection of a computational module from a plurality of computational modules, wherein the computational module is predefined to process module input to provide module output;
configuring the computational module by:
specifying that the module input is website interaction information; and
specifying a function or a parameter customizing how the computational module will process the module input to provide a website-navigation-specific analysis of the website interaction information resulting in customized module output, wherein the website-navigation-specific analysis comprises temporal aggregation of the website interaction information by a temporal aggregation module of the plurality of computational modules, the temporal aggregation module utilizing multiple signals of the website interaction information as input to produce the module output, wherein the website interaction information is weighted with one or more weight vectors; and
assembling the computational module based on the specifying of the module input and the specifying of the function or the parameter, wherein the configuring and assembling are performed by a computer device.
2. The method of claim 1, wherein the website-navigation-specific analysis comprises thresholding of the website interaction information by a thresholding module of the plurality of computational modules.
3. The method of claim 2, wherein the thresholding module evaluates the module input with respect to one or more threshold parameters to produce the module output.
4. The method of claim 1, wherein the website-navigation-specific analysis comprises weighted mixing of the website interaction information by a weighted mix module of the plurality of computational modules.
5. The method of claim 4, wherein the weighted mix module applies one or more weight values to one or more module inputs to produce the module output.
6. The method of claim 1 wherein the website-navigation-specific analysis comprises a logical combination of the website interaction information by a logical combination module of the plurality of computational modules.
7. The method of claim 6, wherein the logical combination module utilizes two module inputs and an OR or AND logical expression to produce the module output.
8. The method of claim 1, further comprising configuring an additional module to receive the customized module output perform an additional website-navigation-specific analysis.
9. The method of claim 1, wherein the module output is utilized to perform targeted advertising.
10. The method of claim 1, wherein the module input includes demographic information related to a user of a particular website.
11. The method of claim 1, wherein the module input includes visitor-specific information related to a user of a particular website.
12. A computer apparatus comprising:
a processor;
a user interface for receiving a user selection of a computational module from a plurality of computational modules, wherein the computational module is predefined to process module input to provide module output;
a configuration component for configuring the computational module by:
specifying that the module input is website interaction information; and
specifying a function or a parameter customizing how the computational module will process the module input to provide a website-navigation-specific analysis of the website interaction information resulting in customized module output, wherein the website-navigation-specific analysis comprises temporal aggregation of the website interaction information by a temporal aggregation module of the plurality of computational modules, the temporal aggregation module utilizing multiple signals of the website interaction information as input to produce the module output, wherein the website interaction information is weighted with one or more weight vectors; and
an assembling component for assembling the computational module based on the specifying of the module input and the specifying of the function or the parameter, wherein the configuring and assembling are performed by a computer device.
13. The computer apparatus of claim 12, further comprising configuring an additional module to automatically select a targeted advertisement based on the module output, wherein the targeted advertisement is provided on the website.
14. A non-transitory computer-readable medium on which is encoded program code, the program code comprising:
program code for receiving a user selection of a computational module from a plurality of computational modules, wherein the computational module is predefined to process module input to provide module output;
program code for configuring the computational module by:
specifying that the module input is website interaction information; and
specifying a function or a parameter customizing how the computational module will process the module input to provide a website-navigation-specific analysis of the website interaction information resulting in customized module output, wherein the website-navigation-specific analysis comprises temporal aggregation of the website interaction information by a temporal aggregation module of the plurality of computational modules, the temporal aggregation module utilizing multiple signals of the website interaction information as input to produce the module output, wherein the website interaction information is weighted with one or more weight vectors; and
program code for assembling the computational module based on the specifying of the module input and the specifying of the function or the parameter, wherein the configuring and assembling are performed by a computer device.