Four-dimensioanl signaling for bandlimited channels
Abstract
We discuss multidimensional signaling for transmission over the satellite channel, i.e., a bandlimited radio channel with nonlinearities. We derive a set of basis signals that are orthogonal and whose bandwidth occupancy is minimal, in the sense that they maximize the power inside a fixed frequency interval (-B,B). Since we remove the assumption that the signals be confined in one symbol interval, the concept of orthogonality must be revisited. We design basis signals that satisfy the following requirements: (a) when passed through their matched filter, the sample sequence has no intersymbol interference; (b) when passed through the filter matched to another basis signal, the sample sequence has no interchannel interference, and (c) their bandwidth occupancy is minimum. The performance of four-dimensional signals designed according to this criterion is evaluated in terms of bandwidth occupancy and error probability over nonlinear satellite channels. Comparisons with two-dimensional modulation schemes (in particular, QPSK) are also made.
- Publication:
-
IEEE Transactions on Communications
- Pub Date:
- February 1994
- Bibcode:
- 1994ITCom..42..403V
- Keywords:
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- Amplitude Modulation;
- Bandwidth;
- Channels (Data Transmission);
- Digital Systems;
- Error Analysis;
- Matched Filters;
- Nonlinear Systems;
- Phase Shift Keying;
- Radio Communication;
- Radio Frequencies;
- Satellite Communication;
- Signal Processing;
- Orthogonality;
- Signal To Noise Ratios;
- Communications and Radar