Display of signals containing inter-symbol interference (ISI). An input signal is modeled as comprising an ideal signal plus ISI plus error. In a first embodiment of the invention, an error signal and an ideal signal are derived from the input signal. The ideal signal is combined with the error signal producing an ideal signal with errors. In a second embodiment of the invention, a first signal comprising the ideal signal plus ISI plus error is derived. A second signal comprising only ISI is derived, and subtracted from the first signal, producing a signal containing the ideal signal plus error.
A method and apparatus for the signal synchronization of an orthogonal frequency division multiplexing system includes a delay conjugate multiplication module, a phase processor and an edge detector. It provides estimates for the boundaries of inter-symbol interference free region by utilizing the characteristics of a guard interval in combination with the techniques of the delay conjugate multiplication module, phase differential operation, symbol-by-symbol average operation, and edge detection. The method determines a fixed optimal threshold for directly separating the inter-symbol interference region in a mobile environment to obtain an inter-symbol interference free version of symbol information.
The frequency bandwidth of a signal is reduced, while retaining the desired signal information, by selectively introducing a controlled distortion to an IQ baseband signal. Selective generation of either a non-distorted complex-valued baseband signal or a distorted complex-valued baseband signal may be based upon values of information bits in the sequence of information bits to be represented by the radio frequency signal. The technique is applicable to both IQ-modulators and polar modulators, thereby allowing cost-efficient and current-efficient polar modulators and/or cost-efficient power amplifiers to be utilized.
A circuit and a method for eliminating interference introduced from an image channel into a desired channel is described. The circuit includes a splitter and an adder. The splitter generates signals split from a received signal having frequency components within the desired and image channel. The adder adds together the signals output from the splitter. The circuit can be used in an TV tuner.
