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An ultra-wide band (UWB) waveform generator and encoder for use in a UWB digital communication system. The encoder multiples each data bit by an n-bit identifying code, (e.g., a user code), resulting in a stream of bits corresponding to each data bit. This stream of bits is referred to as the origin

An ultra-wide band (UWB) waveform generator and encoder for use in a UWB digital communication system. The encoder multiples each data bit by an n-bit identifying code, (e.g., a user code), resulting in a stream of bits corresponding to each data bit. This stream of bits is referred to as the original codeword. The original codeword is passed onto the UWB waveform generator for generation of a UWB waveform that can be transmitted via an antenna. The UWB waveform is made up of shaped wavelets. In one embodiment, the wavelets are bi-phase wavelets, and the UWB waveform generator uses a two-stage differential mixer and a pulse generator. The first stage combines the pulses from the pulse generator with a first derivative codeword derived from the original codeword. The output of this first stage is a wavelet, which is used as input to the second differential mixer along with a second derivative codeword also derived from the original codeword and orthogonal to the first derivative codeword. The output of the second mixer is a wavelet, which represents an inversion of the original codeword. This wavelet is then passed on to an inverting amplifier before it is transmitted via an antenna. By using two derivative codewords at one-half the chipping rate of the original codeword, less power is consumed. An advantage of the two stage mixer system is that it suppresses the noise generated and transmitted by the system.

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An ultra-wide band (UWB) waveform generator and encoder for use in a UWB digital communication system. The encoder multiples each data bit by an n-bit identifying code, (e.g., a user code), resulting in a stream of bits corresponding to each data bit. This stream of bits is referred to as the origin

An ultra-wide band (UWB) waveform generator and encoder for use in a UWB digital communication system. The encoder multiples each data bit by an n-bit identifying code, (e.g., a user code), resulting in a stream of bits corresponding to each data bit. This stream of bits is referred to as the original codeword. The original codeword is passed onto the UWB waveform generator for generation of a UWB waveform that can be transmitted via an antenna. The UWB waveform is made up of shaped wavelets. In one embodiment, the wavelets are bi-phase wavelets, and the UWB waveform generator uses a two-stage differential mixer and a pulse generator. The first stage combines the pulses from the pulse generator with a first derivative codeword derived from the original codeword. The output of this first stage is a wavelet, which is used as input to the second differential mixer along with a second derivative codeword also derived from the original codeword and orthogonal to the first derivative codeword. The output of the second mixer is a wavelet, which represents an inversion of the original codeword. This wavelet is then passed on to an inverting amplifier before it is transmitted via an antenna. By using two derivative codewords at one-half the chipping rate of the original codeword, less power is consumed. An advantage of the two stage mixer system is that it suppresses the noise generated and transmitted by the system. erein the substrate comprises at least a portion of a silicon wafer.3. The actuator of claim 1 wherein the rotatable actuator member is coupled to the substrate with at least one substrate hinge.4. The actuator of claim 1 wherein the rotatable actuator member is coupled to the movable portion of the actuator drive mechanism with at least one actuator hinge.5. The actuator of claim 1 wherein the balancing spring comprises two torsional hinges and a nominally rigid connecting member.6. The actuator of claim 1 wherein the actuator arm is connected to the rotatable actuator member.7. The actuator of claim 5 wherein the actuator arm is connected to the nominally rigid connecting member of the balancing spring.8. The actuator of claim 1 wherein the rotatable actuator member, the movable portion of the actuator drive mechanism, and the balancing spring are formed from a layer of single crystal silicon.9. The actuator of claim 1 wherein the rotatable actuator member, the movable portion of the actuator drive mechanism, and the balancing spring are formed from a layer of polycrystalline silicon.10. The actuator of claim 1 wherein the actuator drive mechanism comprises a parallel-plate electrostatic drive mechanism.11. The actuator of claim 1 wherein the actuator drive mechanism comprises an interdigitated electrostatic drive mechanism.12. The actuator of claim 1 wherein the actuator drive mechanism is selected from the group consisting of an electrostatic drive mechanism, a thermal drive mechanism, a piezoelectric drive mechanism, and a magnetic drive mechanism.13. The actuator of claim 1 wherein a ratio of a displacement of at least a portion of the actuator arm to a displacement of the movable portion of the actuator drive mechanism is greater than two.14. The actuator of claim 1 further comprising: an optical mirror element coupled to the actuator arm. 15. The actuator of claim 1 further comprising: means for applying a first drive voltage to the movable portion of the actuator drive mechanism and a second drive voltage to a fixed portion of the actuator drive mechanism.