1. A system for applying a polar bias modulation having a phase component and an amplitude component to a signal, the system comprising:
a power amplifier (PA) having a plurality of amplifier gain stages, wherein the power amplifier is configured to amplify an input to create an amplifier output signal;
a frequency synthesizer configured to apply a phase modulation to the signal input to the power amplifier, wherein the phase modulation is based upon the phase component of the polar bias modulation; and
an amplitude control circuit comprising a detector configured to receive an indication of the amplifier output as a feedback signal, a control module configured to generate a control signal based upon both the feedback signal and the amplitude component of the polar bias modulation, and a bias circuit configured to adjust a bias signal associated with at least one of the plurality of amplifier gain stages in response to the control signal.
2. The system of claim 1 wherein the signal input to the power amplifier comprises a substantially uniform amplitude.
3. The system of claim 1 further comprising a baseband gain stage coupled to the detector and the control module and configured to adjust the feedback signal.
4. The system of claim 3 wherein the baseband gain stage is configured to adjust the feedback signal based at least in part upon a signal received from a control interface.
5. The system of claim 3 wherein the baseband gain stage is configured to adjust the feedback signal in discrete steps.
6. The system of claim 1 wherein the control module comprises an integrator having a time constant, wherein the integrator is configured to combine the feedback signal and the amplitude component of the polar modulation to create the control signal.
7. The system of claim 6 wherein the time constant of the integrator is adjustable to maintain a substantially constant loop gain of the feedback signal.
8. The system of claim 5 wherein the control module comprises an integrator having a time constant, wherein the integrator is configured to combine the feedback signal and the amplitude component of the polar modulation to create the control signal, and wherein the time constant of the integrator is adjustable with the discrete steps of the baseband gain to maintain a substantially constant loop gain of the feedback signal.
9. The system of claim 1 wherein the plurality of amplifier gain stages comprises a first amplifier gain stage, wherein the bias signal associated with the first stage is a collector voltage.
10. The system of claim 9 wherein the plurality of amplifier gain stages further comprises a second amplifier gain stage, wherein the bias signal associated with the second amplifier gain stage is a base current.
11. The system of claim 10 wherein the bias circuit comprises a voltage-to-current conversion module configured to convert the control signal to the base current of the second amplifier gain stage.
12. The system of claim 1 further comprising an analog-to-digital converter coupled to receive the feedback signal and a digital-to-analog converter configured to provide the control signal to the bias circuit, and wherein the control module comprises digital circuitry logically disposed between the analog-to-digital converter and the digital-to-analog converter.
13. The system of claim 1 wherein the control module comprises an analog integrator and associated bias circuitry.
14. A wireless telephone handset incorporating the system of claim 1.
15. A method of applying a polar modulation having a phase component and an amplitude component to a power amplifier (PA) having an amplifier gain stage, wherein the power amplifier is configured to amplify an input to create an amplifier output signal, the method comprising the steps of:
receiving an indication of the amplifier output as a feedback signal;
generating a control signal based upon both the feedback signal and the amplitude component of the polar bias modulation; and
adjusting a bias signal associated with the amplifier gain stage in response to the control signal.
16. The method of claim 15, further comprising the step applying a phase modulation to the signal input to the power amplifier, wherein the phase modulation is based upon the phase component of the polar bias modulation.
17. The method of claim 15 further comprising the step of adjusting the feedback signal in discrete steps between the receiving step and the generating step.
18. The method of claim 15 wherein the generating step comprises combining the feedback signal and the amplitude component of the polar modulation at an integrator to create the control signal, and wherein the time constant of the integrator is adjustable with the discrete steps of the baseband gain to maintain a substantially constant loop gain of the feedback signal.
19. A circuit configured to execute the method of claim 15.
20. A system for applying a polar modulation having a phase component and an amplitude component to a power amplifier (PA) having an amplifier gain stage, wherein the power amplifier is configured to amplify an input to create an amplifier output signal, the system comprising:
means for receiving an indication of the amplifier output as a feedback signal;
means for generating a control signal based upon both the feedback signal and the amplitude component of the polar bias modulation; and
means for adjusting a bias signal associated with the amplifier gain stage in response to the control signal.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method comprising employing at least one processor to perform each of the steps of:
receiving a plurality of target hashes, each target hash representing a distinct data block of a target object, each distinct code block consisting of a sequence of processor instructions of the target object;
in response to receiving the plurality of target hashes, retrieving a plurality of reference hashes representing a whitelisted data object, and
in response to determining that the plurality of target hashes is not identical to the plurality of reference hashes, and determining that the plurality of target hashes and the plurality of reference hashes share a majority of items, labeling the target object as non-malicious.
2. The method of claim 1, wherein labeling the target object as non-malicious is performed in response to determining a similarity score according to a count of hashes common to both the plurality of target hashes and the plurality of reference hashes.
3. The method of claim 1, wherein each target hash comprises a hash of an opcode pattern, the opcode pattern comprising a sequence of instruction indicators, each instruction indicator indicative of a processor instruction of the distinct code block.
4. The method of claim 1, wherein the sequence of processor instructions consists of between 5 and 50 consecutive processor instructions.
5. The method of claim 3, wherein the sequence of processor instructions consists of between 5 and 15 consecutive processor instructions.
6. The method of claim 1, wherein the sequence of processor instructions starts with a CALL instruction.
7. The method of claim 1, further comprising:
performing a code normalization procedure on the target object to produce a normalized target object, and wherein each distinct code block consists of a sequence of computer instructions of the normalized target object; and
applying a hash function to the distinct code block to produce the target hash.
8. The method of claim 1, wherein the target object comprises a computer file.
9. The method of claim 1, wherein the target object comprises a computer process.
10. A non-transitory computer-readable medium encoding instructions which, when executed by a computer system having at least one processor, cause the computer system to:
receive a plurality of target hashes, each target hash representing a distinct data block of a target object, each distinct code block consisting of a sequence of processor instructions of the target object;
in response to receiving the plurality of target hashes, retrieve a plurality of reference hashes representing a whitelisted data object, and
in response to determining that the plurality of target hashes is not identical to the plurality of reference hashes, and determining that the plurality of target hashes and the plurality of reference hashes share a majority of items, label the target object as non-malicious.
11. The computer-readable medium of claim 10, wherein labeling the target object as non-malicious is performed in response to determining a similarity score according to a count of hashes common to both the plurality of target hashes and the plurality of reference hashes.
12. The computer-readable medium of claim 10, wherein each target hash comprises a hash of an opcode pattern, the opcode pattern comprising a sequence of instruction indicators, each instruction indicator indicative of a processor instruction of the distinct code block.
13. The computer-readable medium of claim 10, wherein the sequence of processor instructions consists of between 5 and 50 consecutive processor instructions.
14. The computer-readable medium of claim 13, wherein the sequence of processor instructions consists of between 5 and 15 consecutive processor instructions.
15. The computer-readable medium of claim 10, wherein the sequence of processor instructions starts with a CALL instruction.
16. The computer-readable medium of claim 10, wherein the instructions further cause the computer system to:
perform a code normalization procedure on the target object to produce a normalized target object, and wherein each distinct code block consists of a sequence of computer instructions of the normalized target object; and
apply a hash function to the distinct code block to produce the target hash.
17. The computer-readable medium of claim 10, wherein the target object comprises a computer file.
18. The computer-readable medium of claim 10, wherein the target object comprises a computer process.
19. A computer system comprising at least one processor configured to form:
means for receiving a plurality of target hashes, each target hash representing a distinct data block of a target object, each distinct code block consisting of a sequence of processor instructions of the target object;
means for retrieving a plurality of reference hashes representing a whitelisted data object in response to receiving the plurality of target hashes, and
means for labeling the target object as non-malicious in response to determining that the plurality of target hashes is not identical to the plurality of reference hashes and determining that the plurality of target hashes and the plurality of reference hashes share a majority of items.
20. The system of claim 19, wherein labeling the target object as non-malicious is performed in response to determining a similarity score according to a count of hashes common to both the plurality of target hashes and the plurality of reference hashes.