Digital automatic gain control with parallel/serial interface for multiple antenna ultra wideband OFDM system

1. An ultra wideband OFDM receiver, comprising:

at least one channel comprising an antenna, a low noise amplifier coupled to the antenna and a variable gain amplifier coupled to each mixed and filtered I and Q output of the low noise amplifier;

a gain controller communicatively coupled to a parallel/serial interface; and

a calculation engine, which is communicatively coupled to the gain controller, and calculates the gain codes during a preamble portion of a packet;

wherein the gain controller transmits gain codes for adjusting gain of the variable gain amplifier to the parallel/serial interface, which is further communicatively coupled to a variable gain amplifier controller;

wherein the gain controller transmits gain codes for adjusting gain of the low noise amplifier to the parallel/serial interface, which is further communicatively coupled to a low noise amplifier controller;

wherein the gain codes include three gain codes per channel corresponding to frequency hops over three bands per channel;

wherein the gain codes are based on received energy at each antenna;

wherein the calculation engine repeatedly calculates the gain codes every set integer number of symbols within a payload portion of the packet.

2. The receiver of claim 1 , wherein the controller looks up the adjustment amounts from a first lookup table, the first lookup table having values calibrated for a low target energy.

3. The receiver of claim 2 , wherein the adjustment amount is modified after lookup by adding a variable amount for a target energy higher than the low target energy.

4. The receiver of claim 1 , wherein the controller looks up the gain codes from a second lookup table, the lookup table having codes calibrated for the receiver.

5. The receiver of claim 1 , wherein the repeating is at least a distance apart to enable a parallel/serial interface and an analog portion of the receiver to settle.

6. The receiver of claim 1 , wherein the gain controller adjusts the low noise amplifiers of each channel based on the received energy.

7. The receiver of claim 1 , wherein the parallel/serial interface shifts the gain code serially into registers of the variable gain amplifier controller.

8. The receiver of claim 1 , wherein the parallel/serial interface shifts the gain code serially into registers of the low noise amplifier controller.

9. The receiver of claim 7 , wherein a parallel/serial interface is configured to monitor contents of the registers for diagnostic purposes.

10. A method, comprising:

receiving an ultra wideband signal at least one channel comprising an antenna, a low noise amplifier coupled to the antenna and a variable gain amplifier coupled to each mixed and filtered I and Q output of the low noise amplifier;

adjusting gain of the variable gain amplifiers of each channel with a gain controller communicatively coupled to a parallel/serial interface;

calculating the gain codes during a preamble portion of a packet; and

repeatedly calculating the gain codes every set integer of symbols within a payload portion of the packet;

wherein the gain controller transmits gain codes for adjusting gain of the variable gain amplifier to the parallel/serial interface further communicatively coupled to a variable gain amplifier controller;

wherein the gain codes include three gain codes per channel corresponding to frequency hops over three bands per channel;

wherein the gain codes are based on received energy at each antenna.

11. The method of claim 10 , further comprising looking up the adjustment amounts from a first lookup table, the first lookup table having values calibrated for a low target energy.

12. The method of claim 11 , wherein the adjustment amount is modified after lookup by adding a variable amount for a target energy higher than the low target energy.

13. The method of claim 10 , wherein the controller looks up the gain codes from a second lookup table, the lookup table having codes calibrated for the system.

14. The method of claim 10 , wherein the repeating is at least a distance apart to enable a parallel/serial interface and an analog portion of the receiver to settle.

15. The method of claim 10 , further comprising adjusting the low noise amplifiers of each channel based on the received energy.

16. The method of claim 10 , further comprising shifting the gain code serially into registers of the variable gain amplifier controller.

17. The receiver of claim 10 , further comprising shifting the gain code serially into registers of the low noise amplifier controller.

18. The method of claim 16 , further comprising monitoring contents of the registers for diagnostic purposes.