Unified modulator for continuous phase modulation and phase-shift keying

An apparatus comprising:

• a plurality of filters for a plurality of pulse shaping functions, each filter having an impulse response corresponding to one of the plurality of pulse shaping functions, wherein the plurality of filters are used to generate a plurality of waveforms for a plurality of modulation schemes, and wherein a waveform for each modulation scheme is generated with a different set of one or more filters selected from among the plurality of filters;
• a summer operative to sum outputs of enabled ones of the plurality of filters to generate a modulator output;
• and
• a plurality of pre-processors, each pre-processor operative to receive input bits for one of the plurality of modulation schemes and provide symbols for one of the plurality of filters,
• wherein the plurality of filters comprises a first filter operative to receive first symbols for a first modulation scheme or second symbols for a second modulation scheme and a second filter operative to receive and filter third symbols for the first modulation scheme and provide a second filter output, and wherein initial first and third symbols are derived based on an initial phase value selected to provide a smooth phase for the modulator output when transitioning from the second modulation scheme to the first modulation scheme by performing adding and rounding functions for selected second modulation scheme symbols.

A method of generating a modulated signal, comprising:

• filtering with a first filter first symbols for a first modulation scheme or second symbols for a second modulation scheme to generate a first filter output;
• filtering with a second filter third symbols for the first modulation scheme to generate a second filter output;
• and
• summing the first and second filter outputs to generate a modulator output, and wherein the modulator output is used to generate the modulated signal;
• wherein initial first and third symbols are derived based on an initial phase value selected to provide a smooth phase for the modulator output when transitioning from the second modulation scheme to the first modulation scheme by performing adding and rounding functions for selected second modulation scheme symbols.

An apparatus comprising:

• means for filtering with a first filter first symbols for a first modulation scheme or second symbols for a second modulation scheme to generate a first filter output;
• means for filtering with a second filter third symbols for the first modulation scheme to generate a second filter output;
• and
• means for summing the first and second filter outputs to generate a modulator output, wherein the modulator output is used to generate the modulated signal,
• wherein initial first and third symbols are derived based on an initial phase value selected to provide a smooth phase for the modulator output when transitioning from the second modulation scheme to the first modulation scheme by performing adding and rounding functions for selected second modulation scheme symbols.

A non-transitory computer-readable medium having a computer program, which when executed by at least one processor, operates to generate a modulated signal, the computer program comprising:

• instructions for filtering with a first filter first symbols for a first modulation scheme or second symbols for a second modulation scheme to generate a first filter output;
• instructions for filtering with a second filter third symbols for the first modulation scheme to generate a second filter output;
• and
• instructions for summing the first and second filter outputs to generate a modulator output, and wherein the modulator output is used to generate the modulated signal;
• wherein initial first and third symbols are derived based on an initial phase value selected from a transition lookup table to provide a smooth phase for the modulator output when transitioning from the second modulation scheme to the first modulation scheme by performing adding and rounding functions for selected second modulation scheme symbols.

At least one processor configured to perform a method of generating a modulated signal, the method comprising:

• filtering with a first filter first symbols for a first modulation scheme or second symbols for a second modulation scheme to generate a first filter output;
• filtering with a second filter third symbols for the first modulation scheme to generate a second filter output;
• and
• summing the first and second filter outputs to generate a modulator output, and wherein the modulator output is used to generate the modulated signal;
• wherein initial first and third symbols are derived based on an initial phase value selected to provide a smooth phase for the modulator output when transitioning from the second modulation scheme to the first modulation scheme by performing adding and rounding functions for selected second modulation scheme symbols.