Power control circuitry for a TDMA radio frequency transmitter

A radio communicating via a plurality of radio channels, said radio comprising in combination:

• an antenna for receiving and transmitting signals via the plurality of radio channels;
• a receiver coupled to the antenna for receiving a receive signal via one of the plurality of radio channels;
• a transmitter coupled to the antenna for transmitting a radio frequency (RF) output via one of the plurality of radio channels, said transmitter further including power control circuitry responsive to a transmit signal, level control signals, a timing signal defining a series of transmit time intervals, and a supply voltage from a signal source for maintaining during the transmit time intervals the average magnitude of the RF output signal at a power level selected from a plurality of power levels by the level control signals, said supply voltage having a magnitude between a predetermined minimum voltage and a predetermined maximum voltage, said power control circuitry further comprising:
• a memory for storing the value of a gain control signal;
• adjusting circuitry having variable gain for adjusting the transmit signal during the transmit time intervals substantially in proportion to the stored value of the gain control signal to produce an adjusted transmit signal, said adjusting circuitry substantially blocking the transmit signal at times other than those during the transmit time intervals;
• an amplifier coupled to the supply voltage for amplifying the adjusted transmit signal to produce the RF output signal;
• a voltage detector for detecting the magnitude of the supply voltage;
• a temperature detector for detecting the temperature of the power control circuitry;
• a power detector coupled to the RF output signal for generating an output signal having a value related to the magnitude of the forward power of the RF output signal;
• and
• control circuitry coupled to the power detector for sampling the value of the output signal substantially at the end of each transmit time interval, adjusting the value of the gain control signal in response to the difference between the sampled value of the output signal and the selected power level, and storing the adjusted value of the gain control signal in the memory, said control further being coupled to the temperature detector for adjusting the gain control signal by a first predetermined amount substantially at the beginning of each transmit time interval when the detected temperature is greater than a predetermined temperature, and said control circuitry further being coupled to the voltage detector for adjusting the gain control signal by a second predetermined amount substantially at the beginning of at least the first one of the series of transmit time intervals when the detected magnitude of the supply voltage is less than a predetermined magnitude.

Power control circuitry responsive to a transmit intermediate frequency (IF) signal, level control signals, a timing signal defining a series of transmit time intervals, and a supply voltage from a signal source for maintaining during the transmit time intervals the average magnitude of a radio frequency (RF) output signal at a power level selected from a plurality of power levels by the level control signals, said supply voltage having a magnitude between a predetermined minimum voltage and a predetermined maximum voltage, said power control circuitry comprising:

• reference circuitry for generating an RF reference signal;
• a memory for storing the value of a gain control signal;
• adjusting circuitry having variable gain for adjusting the transmit IF signal during the transmit time intervals substantially in proportion to the stored value of the gain control signal to produce an adjusted transmit IF signal, said adjusting circuitry substantially blocking the transmit IF signal at times other than those during the transmit time intervals;
• a mixer for combining the adjusted transmit IF signal and the RF reference signal to produce an RF transmit signal;
• an amplifier coupled to the supply voltage for amplifying the RF transmit signal to produce the RF output signal;
• an antenna coupled to the amplifier for transmitting the RF output signal;
• a voltage detector for detecting the magnitude of the supply voltage;
• a temperature detector for detecting the temperature of the power control circuitry;
• a first power detector coupled to the RF output signal for generating a first output signal having a value related to the magnitude of the forward power of the RF output signal;
• and
• control circuitry coupled to the first power detector for sampling the value of the first output signal substantially at the end of each transmit time interval, adjusting the value of the gain control signal in response to the difference between the sampled value of the first output signal and the selected power level, and storing the adjusted value of the gain control signal in the memory, said control circuitry further being coupled to the temperature detector for adjusting the gain control signal by a first predetermined amount substantially at the beginning of each transmit time interval when the detected temperature is greater than a predetermined temperature, and said control circuitry further being coupled to the voltage detector for adjusting the gain control signal by a second predetermined amount substantially at the beginning of at least the first one of the series of transmit time intervals when the detected magnitude of the supply voltage is less than a predetermined magnitude.

A radio communicating via a plurality of radio channels, said radio comprising in combination:

• an antenna for receiving and transmitting signals via the plurality of radio channels;
• a receiver coupled to the antenna for receiving a receive signal via one of the plurality of radio channels;
• a transmitter coupled to the antenna for transmitting a radio frequency (RF) output via one of the plurality of radio channels, said transmitting further including power control circuitry responsive to a transmit intermediate frequency (IF) signal, level control signals, a timing signal defining a series of transmit time intervals, and a supply voltage from a signal source for maintaining during the transmit time intervals the average magnitude of the RF output signal at a power level selected from a plurality of power levels by the level control signals, said supply voltage having a magnitude between a predetermined minimum voltage and a predetermined maximum voltage, said power control circuitry further comprising:
• reference circuitry for generating an RF reference signal;
• a memory for storing the value of a gain control signal;
• adjusting circuitry having variable gain for adjusting the transmit IF signal during the transmit time intervals substantially in proportion to the stored value of the gain control to produce an adjusted transmit IF signal, said adjusting circuitry substantially blocking the transmit IF signal at times other than those during the transmit time intervals;
• a mixer for combining the adjusted transmit IF signal and the RF reference signal to produce an RF transmit signal;
• an amplifier coupled to the supply voltage for amplifying the RF transmit signal to produce the RF output signal;
• a voltage detector for detecting the magnitude of the supply voltage;
• a temperature detector for detecting the temperature of the power control circuitry;
• a power detector coupled to the RF output signal for generating an output signal having a value related to the magnitude of the forward power of the RF output signal;
• and
• control circuitry coupled to the power detector for sampling the value of the output signal substantially at the end of each transmit time interval, adjusting the value of the gain control signal in response to the difference between the sampled value of the output signal and the selected power level, and storing the adjusted value of the gain control signal in the memory said control circuitry further being coupled to the temperature detector for adjusting the gain control signal by a first predetermined amount substantially at the beginning of each transmit time interval when the detected temperature is greater than a predetermined temperature, and said control circuitry further being coupled to the voltage detector for adjusting the gain control signal by a second predetermined amount substantially at the beginning of at least the first one of the series of transmit time intervals when the detected magnitude of the supply voltage is less than a predetermined magnitude.

Power control circuitry responsive to a transmit signal, level control signals, and a supply voltage from a signal source for maintaining the magnitude of a radio frequency (RF) output signal at a power level selected from a plurality of power levels by the level control signals, said supply voltage having a magnitude between a predetermined minimum voltage and a predetermined maximum voltage, said power control circuitry comprising:

• adjusting circuitry having variable gain for adjusting the transmit signal during a series of transmit time intervals defined by a timing signal substantially in proportion to the value of the gain control signal to produce an adjusted transmit signal;
• an amplifier coupled to the supply voltage for amplifying the adjusted transmit signal to produce the RF output signal;
• an antenna coupled to the amplifier for transmitting the RF output signal;
• a voltage detector for detecting the magnitude of the supply voltage;
• a temperature detector for detecting the temperature of the power control circuitry;
• a first power detector coupled to the RF output signal for generating a first output signal having a value related to the magnitude of the forward power of the RF output signal;
• and
• control circuitry coupled to the first power detector for sampling the value of the first output signal substantially at a plurality of time intervals, and adjusting the value of the gain control signal in response to the difference between the sampled value of the first output signal and the selected power level, said control circuitry further being coupled to the temperature detector for adjusting the gain control signal by a first predetermined amount substantially at the beginning of each transmit time interval when the detected temperature is greater than a predetermined temperature, and said control circuitry further being coupled to the voltage detector for adjusting the gain control signal by a second predetermined amount substantially at the beginning of at least the first one of the series of transmit time intervals when the detected magnitude of the supply voltage is less than a predetermined magnitude.

A radio communicating via a plurality of radio channels, said radio comprising in combination:

• an antenna for receiving and transmitting signals via the plurality of radio channels;
• a receiver coupled to the antenna for receiving a receive signal via one of the plurality of radio channels;
• a transmitter coupled to the antenna for transmitting a radio frequency (RF) output via one of the plurality of radio channels, said transmitting further including power control circuitry responsive to a transmit signal, level control signals, and a supply voltage from a signal source for maintaining the magnitude of the RF output signal at a power level selected from a plurality of power levels by the level control signals, said supply voltage having a magnitude between a predetermined minimum voltage and a predetermined maximum voltage, said power control circuitry comprising:
• adjusting circuitry having variable gain for adjusting the transmit signal during the a series of transmit time intervals defined by a timing signal substantially in proportion to the stored value of the gain control signal to produce an adjusted transmit signal;
• an amplifier coupled to the supply voltage for amplifying the adjusted transmit signal to produce the RF output signal;
• a voltage detector for detecting the magnitude of the supply voltage;
• a temperature detector for detecting the temperature of the power control circuitry;
• a power detector coupled to the RF output signal for generating an output signal having a value related to the magnitude of the forward power of the RF output signal;
• and
• control circuitry coupled to the power detector for sampling the value of the output signal substantially at a plurality of time intervals, and adjusting the value of the gain control signal in response to the difference between the sampled value of the output signal and the selected power level, said control circuitry further being coupled to the temperature detector for adjusting the gain control signal by a first predetermined amount substantially at the beginning of each transmit time interval when the detected temperature is greater than a predetermined temperature, and said control circuitry further being coupled to the voltage detector for adjusting the gain control signal by a second predetermined amount substantially at the beginning of at least the first one of the series of transmit time intervals when the detected magnitude of the supply voltage is less than a predetermined magnitude.