Wireless telecommunication digital receiver

A digital receiver for receiving an RF signal has a conventional RF to intermediate frequency (IF) converter. The IF signal, however, is amplified with a limit on its amplitude. In addition, a Receive Signal Strength Intensity (RSSI) signal is generated. The RSSI signal contains the envelope information of the modulated IF signal. The IF amplitude limited signal containing phase information, is then digitized and a complex baseband signal is produced. The complex baseband signal is then combined with the RSSI signal to restore the amplitude information of the modulated IF signal in the complex baseband signal. The restored complex baseband signal can be equalized with a conventional equalizer to remove intersymbol interference. A conventional symbol detector detects the symbol in this signal stream.

What is claimed is:

1. A telecommunication receiver for receiving a wireless transmitted electromagnetic signal, said receiver comprising:

antenna means for receiving said wireless transmitted electromagnetic signal and for converting same to a radio frequency (RF) signal;

means for converting said RF signal into an intermediate frequency (IF) signal, having an amplitude; and for limiting said amplitude and for generating a receive signal strength intensity (RSSI) signal;

bandpass converting means for receiving said amplitude limited IF signal and said RSSI signal; said converting means comprising:

means for converting said amplitude limited IF signal to a plurality of baseband signals;

means for digitizing each of said plurality of baseband signals at a sampling rate to produce a plurality of digitized baseband signals;

means for combining said plurality of digitized baseband signals to produce a complex signal S(t) in accordance with

S(t)=I(t)+jQ(t) where I.sup.2 (t)+Q.sup.2 (t)=constant

where I,Q are said plurality of digitized baseband signals;

means for digitizing said RSSI signal at said same sampling rate, to produce a digitized RSSI signal;

means for multiplying said digitized RSSI signal with said complex signal to produce a complex baseband signal;

means for equalizing said complex baseband signal by removing intersymbol interference; and

means for detecting symbols in said equalized complex baseband signal.

2. A telecommunication receiver for receiving a wireless transmitted electromagnetic signal, said receiver comprising:

antenna means for receiving said wireless transmitted electromagnetic signal and for converting same to a radio frequency (RF) signal;

means for converting said RF signal into an intermediate frequency (IF) signal, having an amplitude; and for limiting said amplitude and for generating a receive signal strength intensity (RSSI) signal;

bandpass converting means for receiving said amplitude limited IF signal and said RSSI signal, said converting means comprising:

means for digitizing said amplitude limited IF signal at a first sampling rate to produce a digitized IF signal;

means for converting said digitized IF signal to a plurality of digitized baseband signals;

means for combining said plurality of digitized baseband signals to produce a complex signal S(t) in accordance with

S(t)=I(t)+jQ(t) where I.sup.2 (t)+Q.sup.2 (t)=constant

where I,Q are said plurality of digitized baseband signals;

means for digitizing said RSSI signal, at a second sampling rate, to produce a digitized RSSI signal;

means for multiplying said digitized RSSI signal with said complex signal to produce a complex baseband signal;

means for equalizing said complex baseband signal by removing intersymbol interference; and

means for detecting symbols in said equalized complex baseband signal.

3. The receiver of claim 2 wherein said first sampling rate is four times the second sampling rate.

4. A telecommunication receiver for receiving a wireless transmitted electromagnetic signal, said receiver comprising:

a plurality of spaced apart antenna means for receiving said wireless transmitted electromagnetic signal and for converting same to a plurality of radio frequency (RF) signals;

a plurality of means for converting said plurality of RF signals into a plurality of intermediate frequency (IF) signals each having an amplitude and for limiting the amplitude of each IF signal and for generating a receive signal strength intensity (RSSI) signal associated with each IF signal;

bandpass converting means for receiving said plurality of IF signals, and the RSSI signal associated with each IF signal, said converting means comprising:

means for converting each IF signal into a plurality of baseband signals;

means for digitizing each of said plurality of baseband signals of each IF signal at a sampling rate to produce a plurality of digitized baseband signals;

means for combining said plurality of digitized baseband signals for each IF signal to produce a complex signal S(t) in accordance with

S(t)=I(t)+jQ(t) where I.sup.2 (t)+Q.sup.2 (t)=constant

where I,Q are said plurality of digitized baseband signals for each IF signal;

means for digitizing each of said RSSI signal associated with each IF signal, at said same sampling rate, to produce a digitized RSSI signal;

means for multiplying each of said digitized RSSI signal with its associated complex signal to produce a complex baseband signal;

means for combining said complex baseband signals into a symbol signal; and

means for detecting symbols in said symbol signal.

5. A telecommunication receiver for receiving a wireless transmitted electromagnetic signal, said receiver comprising:

a plurality of spaced apart antenna means for receiving said wireless transmitted electromagnetic signal and for converting same to a plurality of radio frequency (RF) signals;

a plurality of means for converting said plurality of RF signals into a plurality of intermediate frequency (IF) signals each having an amplitude and for limiting the amplitude of each IF signal and for generating a receive signal strength intensity (RSSI) signal associated with each IF signal;

bandpass converting means for receiving said plurality of IF signals, and the RSSI signal associated with each IF signal; said converting means comprising:

means for digitizing each IF signal at a first sampling rate to produce a digitized IF signal;

means for converting each digitized IF signal into a plurality of digitized baseband signals;

means for combining each of said plurality of digitized baseband signals associated with each IF signal to produce a complex signal S(t) in accordance with

S(t)=I(t)+jQ(t) where I.sup.2 (t)+Q.sup.2 (t)=constant

where I,Q are said plurality of digitized baseband signals for each IF signal;

means for digitizing each RSSI signal at a second sampling rate, lower than said first sampling rate, to produce a digitized RSSI signal;

means for multiplying each of said digitized RSSI signal with its associated complex signal to produce a complex baseband signal;

means for combining said complex baseband signals into a symbol signal; and

means for detecting symbols in said symbol signal.

6. The receiver of claim 5 wherein said first sampling rate is four times the second sampling rate.

7. A method of detecting symbol signals in a wireless transmitted electromagnetic signal, said method comprising:

receiving said wireless transmitted electromagnetic signal and converting same to radio frequency (RF) signal;

converting said RF signal into an intermediate frequency (IF) signal, having an envelope and an amplitude;

limiting the amplitude of said IF signal to produce an amplitude limited IF signal;

detecting the envelope of the IF signal to generate a receive signal strength intensity (RSSI) signal;

generating a digitized baseband signal containing only the phase of said IF signal from said amplitude limited IF signal;

processing said digitized baseband signal by said RSSI signal to generate a complex baseband signal having the envelope of said IF signal;

equalizing said complex baseband signal by removing intersymbol interference; and

detecting symbols in said equalized complex baseband signal.

8. The method of claim 7 wherein said generating step further comprises:

converting said limited IF signal to a plurality of baseband signals;

digitizing said plurality of baseband signals at a sampling rate to produce a plurality of digitized baseband signals;

combining said plurality of digitized baseband signals to produce a complex signal S(t), in accordance with

S(t)=I(t)+jQ(t) where I.sup.2 (t)+Q.sup.2 (t)=constant

where I,Q are said plurality of baseband signals;

digitizing said RSSI signal, at the same sampling rate to produce a digitized RSSI signal.

9. The method of claim 7 wherein said generating step further comprises:

digitizing said amplitude limited IF signal at a first sampling rate to produce a digitized IF signal;

converting said digitized IF signal into a plurality of digitized baseband signals;

combining said plurality of digitized baseband signals to produce a complex signal S(t), in accordance with

S(t)=I(t)+jQ(t) where I.sup.2 (t)+Q.sup.2 (t)=constant

where I,Q are a plurality of digitized baseband signals;

digitizing said RSSI signal at a second sampling rate to produce a digitized RSSI signal.

10. The method of claim 9 wherein said first sampling rate is four times said second sampling rate.