Bit error rate estimator
AssigneeMotorola, Inc.
InventorLansing M. Carson
Life of this patent
Estimating the term…
Abstract
A bit error estimator produces a count of detected errors in a TDMA burst data radio transmission. An input phase signal is translated into one of a number of quadrants. A feedback phase estimator then averages the difference between the input phase signal and an output phase signal in a feedback loop to determine an average of the signal differences. The bit error rate estimator then produces a pseudo error count over a predefined time period which is proportional to the number and magnitude of any bit errors in the TDMA burst data radio transmission.
Claims17
A bit error rate estimator apparatus comprising:
- a QPSK decision mapper for mapping an input phase signal into one of four quadrants and producing an output phase signal representing said one of four quadrants;
- a feedback phase estimator for averaging a difference signal between said input phase signal and said output phase signal, said feedback phase estimator means coupled to said QPSK decision mapper;
- a bit error rate estimator for producing a pseudo error count, over a predefined time period of bit errors of said input phase signal, proportional to a number of said bit errors and to a magnitude of said bit errors of said input phase signal, said bit error rate estimator coupled to said feedback phase estimator;
- said input phase signal including quadrature I and Q channel input signals;
- an arc tangent function for receiving said I and Q channel input signals and producing an arc tangent function signal of said Q channel input signal divided by said I channel input signal
- said OPSK decision mapper includes a first subtractor for subtracting said arc tangent function signal from said output phase signal to produce an angle error signal, said first subtractor coupled to said arc tangent function, to said feedback phase estimator and to said OPSK decision mapper;
- and
- a second subtractor for subtracting said arc tangent function signal from said output phase signal to produce said difference signal, said second subtractor coupled to said feedback phase estimator.
In a radio, a bit error rate estimator apparatus comprising:
- a QPSK decision mapper for mapping an input phase signal into one of four quadrants and producing an output phase signal representing said one of four quadrants;
- a feedback phase estimator for averaging a difference signal between said input phase signal and said output phase signal, said feedback phase estimator means coupled to said QPSK decision mapper;
- a bit error rate estimator for producing a pseudo error count, over a predefined time period of bit errors of said input phase signal, proportional to a number of said bit errors and to a magnitude of said bit errors of said input phase signal, said bit error rate estimator coupled to said feedback phase estimator;
- said input phase signal including quadrature I and Q channel input signals;
- an arc tangent function for receiving said I and Q channel input signals and producing an arc tangent function signal of said Q channel input signal divided by said I channel input signal and;
- said OPSK decision mapper includes a first subtractor for subtracting said arc tangent function signal from said output phase signal to produce an angle error signal, said first subtractor coupled to said arc tangent function, to said feedback phase estimator and to said OPSK decision mapper;
- and
- a second subtractor for subtracting said arc tangent function signal from said output phase signal to produce said difference signal, said second subtractor coupled to said feedback phase estimator.
Dependencies are inferred from the claim text.