| 摘要 |
Communications systems and/or methods are disclosed that may be used to convey information by forming, and then using, a plurality of frequency agile baseband waveforms, wherein any two different waveforms of the plurality of frequency agile baseband waveforms comprise an orthogonality therebetween. The systems/methods disclosed can convey information by mapping an information sequence into a baseband waveform sequence that includes waveforms of the plurality of baseband waveforms, and by transmitting the baseband waveform sequence. Such systems and/or methods can provide extreme privacy, cognitive radio capability, robustness to fading and interference, communications performance associated with M-ary orthonormal signaling and/or high multiple-access capacity. |
| 主权项 |
1. A communications method comprising:
providing a frequency content by Fourier transforming a signal; then forming at baseband a desired spectrum shape that differs from the frequency content, responsive to the frequency content; then generating at baseband a waveform by inverse Fourier transforming the desired spectrum shape; and then transmitting the waveform by using a plurality of elements thereof, sequentially one after another, to modulate a single carrier frequency; wherein generating at baseband a waveform by inverse Fourier transforming the desired spectrum shape comprises: generating at baseband a discrete time-domain waveform U(nT) without resorting to chipping of the inverse Fourier transform of the desired spectrum shape with a binary waveform; wherein n denotes a discrete time index of U(nT), wherein n=1, 2, . . . , N; and NT≦τ; wherein τdenotes a time span of the discrete time-domain waveform U(nT); and wherein T>0; and wherein transmitting the waveform by using a plurality of elements thereof, sequentially one after another, to modulate a single carrier frequency comprises: using substantially all of the elements of U(nT) sequentially to modulate the single carrier frequency by using U(T), followed by using U(2T), . . . , followed by using U(NT). |
