Transceiver for communicating over different media types
View Patent ↗One embodiment of the present invention relates to a transceiver. The transceiver includes a transmitter having a first transmission path configured to transmit a digital baseband signal over a wireline medium. In addition, the transmitter has a second transmission path configured to transmit a radio frequency signal over a wireless medium. Other systems and methods are also disclosed.
1. A transmitter, comprising:
a first transmission path adapted to selectively transmit a baseband signal over a baseband frequency band or a passband signal over a passband frequency band supported by a wireline medium;
a second transmission path adapted to transmit a radio frequency (RF) signal over a wireless medium;
an adjustable frequency source adapted to selectively generate a signal having a frequency in the baseband frequency band or the passband frequency band, wherein the baseband frequency band and the passband frequency band are different from one another;
a mixer adapted to selectively provide the baseband signal and the passband signal over the first transmission path as a function of the frequency; and
a radio frequency (RF) modulator downstream of the mixer, and adapted to up-convert the baseband signal or the passband signal to the RF signal.
2. The transmitter of claim 1 , where the mixer is adapted to receive a first frequency to generate the baseband signal and a second frequency to generate the passband signal, the first frequency being greater than the second frequency.
3. The transmitter of claim 1 , where the RF modulator comprises:
first and second digital-to-analog converters adapted to receive real and imaginary components, respectively, of the baseband or passband signal and provide respective analog signals as a function thereof;
first and second mixers adapted to up shift the respective analog signals to RF signals; and
an adder adapted to combine the RF signals.
4. The transmitter of claim 1 , further comprising:
an inverse discrete Fourier transform (IDFT) block adapted to receive a number (N) of input signals and provide a sampled signal as a function of the input signals; and
an interpolator adapted to provide an interpolated signal as a function of the sampled signal; and
another mixer adapted to receive the interpolated signal and provide the baseband or passband signal as a function thereof.
5. The transmitter of claim 4 , where the transmitter is adapted to transmit a real portion of the baseband or passband signal while discarding an imaginary portion of the baseband or passband signal.
6. The transmitter of claim 4 , where the IDFT block receives 2N input signals, where N+1 input signals are zeros and N−1 input signals are symbol vector elements.
7. The transmitter of claim 1 , further comprising:
a RF modulator adapted to up-convert the baseband signal or the passband signal to the RF signal.
8. The transmitter of claim 7 , where the RF modulator comprises:
first and second digital-to-analog converters adapted to receive real and imaginary components, respectively, of the baseband or passband signal and provide respective analog signals as a function thereof;
first and second mixers adapted to up shift the respective analog signals to RF signals; and
an adder adapted to combine the RF signals.
9. The transmitter of claim 1 , where the transmitter is configured to communicate using both orthogonal-frequency-division multiplexing (OFDM) and discrete mufti-tone (DMT) communication.
10. The transmitter of claim 4 , wherein the IDFTblock is adapted to receive a number (2*N) of input signals, where N corresponds to the number of carriers over which data is to be transmitted; and
where approximately N input signals are complex symbol vector elements and where approximately N input signals are zeros.
11. The transmitter of claim 10 , where the N input signals that are zeros are on successive inputs.
12. The transmitter of claim 10 , where approximately half of the N complex symbol vector elements are loaded on lowermost carriers and approximately half of the N complex symbol vector elements are located on uppermost carriers, and where the zeros are arranged between the uppermost carriers and lowermost carriers.
13. The transmitter of claim 10 , where the transmitter is adapted to transmit a signal, s(m), according to the following relation:
s
(
m
)
=
1
2
N
∑
k
=
0
N
-
1
(
x
k
(
I
)
cos
(
j
2
π
k
2
N
m
)
-
x
k
(
Q
)
sin
(
j
2
π
k
2
N
m
)
)
.
14. A method of modulating a signal in a transmitter, comprising:
providing complex vector symbols elements;
mixing, at a mixing component, the complex vector symbol elements with a first frequency signal in a baseband frequency band at a first time to provide a baseband signal on a first transmission path of the transmitter;
mixing, at the mixing component, the complex vector symbol elements with a second frequency signal in a passband frequency band at a second time to provide a passband signal on the first transmission path of the transmitter, wherein the first time and the second time are different, and wherein the baseband frequency band the passband frequency band are different; and
up-shifting the complex vector symbol elements to provide a radio frequency (RF) signal on a second transmission path of the transmitter.
15. The method of claim 14 , where the complex vector symbol elements are provided in I-Q format.