1. A fixing tool for holding a component on a chassis, the chassis having an upper surface, a lower surface, a thickness, and first and second edges at least partially defining a fitting hole, the fixing tool comprising:
a holding portion; and
a fitting portion formed integrally with said holding portion, the fitting portion receivable by the fitting hole to fix said holding portion to the chassis, said fitting portion including
a post projecting for a length equal to not less than the chassis thickness,
a clamp plate formed at a distal end of said post and insertable through the fitting hole,
an elastic press piece elastically engagable with the upper surface of the chassis when the clamp plate is inserted through the fitting hole, and
a lockingunlocking piece formed at a portion of said elastic press piece;
wherein when said clamp plate is inserted through the fitting hole the clamp plate is moveable in a first direction to engage the lower surface along the first edge, thereby engaging said elastic press piece and the upper surface, and engaging said lockingunlocking piece with at least a portion of the second edge, and wherein moving said lockingunlocking piece in a direction away from the upper surface disengages said lockingunlocking piece from the second edge and removes the lockingunlocking piece from the fitting hole.
2. A fixing tool for holding a component on a chassis, the chassis having an upper surface, a lower surface, a thickness, and first and second edges at least partially defining a fitting hole, the fixing tool comprising:
a holding portion; and
a fitting portion formed integrally with said holding portion, the fitting portion receivable by the fitting hole to fix said holding portion to the chassis, said fitting portion including:
a post projecting for a length equal to not less than the chassis thickness,
a clamp plate formed at a distal end of said post and insertable through the fitting hole,
an elastic press piece elastically engagable with the upper surface of the chassis when the clamp plate is inserted through the fitting hole,
a lockingunlocking piece formed at a portion of said elastic press piece, and
an elastic piece engagable with the first edge of the fitting hole, and
wherein when said clamp plate is inserted through the fitting hole the clamp plate is moveable in a first direction to engage the lower surface along the first edge, thereby engaging said elastic press piece and the upper surface, and engaging said lockingunlocking piece with at least a portion of the second edge, and wherein the elastic piece biases said clamp plate in a second direction opposite the first direction.
3. The fixing tool according to claim 1, further comprising an elastic piece engagable with the first edge when said clamp plate is received by the fitting hole, and biasing said clamp plate in a second direction opposite the first direction.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method performed in a full-duplex transceiver, comprising:
generating a combined radio-frequency communication signal including an outgoing radio-frequency communication signal having a center frequency, and a radio-frequency test signal having a center frequency different from the center frequency of the outgoing radio-frequency communication signal;
amplifying the combined radio-frequency communication signal using a power amplifier;
transmitting the amplified combined radio-frequency communication signal from a transmit antenna;
receiving an incoming radio-frequency signal, wherein the incoming radio-frequency signal includes a radio-frequency test component caused by the transmitted radio-frequency test signal and a self-interference component caused by the transmitted radio-frequency communication signal;
demodulating at least the radio-frequency test component to obtain a demodulated test component;
sampling the demodulated test component to obtain a sampled test component; and
processing the sampled test component to determine nonlinear distortion introduced by the power amplifier.
2. The method of claim 1, wherein the demodulated test component includes an in-phase component and a quadrature component, and wherein the sampling of the first demodulated signal includes alternately sampling the in-phase component and the quadrature component.
3. The method of claim 2, wherein the sampling of the first demodulated signal is performed by a single analog-to-digital converter.
4. The method of claim 1, wherein the radio-frequency test component includes an in-phase component and a quadrature component, wherein demodulating of the radio-frequency test component includes:
generating a radio-frequency local oscillator signal;
alternating the phase of the radio-frequency local oscillator signal to generate an alternating-phase local oscillator signal; and
mixing the alternating-phase local oscillator signal with the radio-frequency test component.
5. The method of claim 4, wherein the alternating of the phase of the radio-frequency local oscillator signal includes alternately shifting the phase of the local-oscillator signal by a first phase shift and a second phase shift, and wherein the first and second phase shifts are separated by 90\xb0.
6. The method of claim 4, wherein the sampling of the first demodulated signal is performed by a single analog-to-digital converter.
7. The method of claim 4, wherein the alternating of the phase of the radio-frequency local oscillator signal is performed using a Schiffman phase shifter.
8. The method of claim 1, further comprising:
generating a radio-frequency corrective signal; and
combining the radio-frequency corrective signal with the incoming radio-frequency signal to cancel at least a portion of the self-interference component.
9. The method of claim 8, wherein the radio-frequency corrective signal does not cancel the radio-frequency test component.
10. The method of claim 1, wherein the sideband radio frequency test signal is a frequency-shifted replica of the radio frequency communication signal.
11. The method of claim 1, wherein the sideband radio frequency test signal has a power substantially less than the power of the radio frequency communication signal and substantially greater than the power of the desired radio-frequency signal component.
12. The method of claim 1, wherein the sideband radio frequency test signal has a power at least 20 dB less than the power of the radio frequency communication signal and at least 20 dB greater than the power of the desired radio-frequency signal component.
13. The method of claim 1:
wherein the combined radio-frequency communication signal further includes a second radio-frequency test signal, wherein the first radio-frequency test signal has a center frequency lower than the center frequency of the outgoing radio-frequency communication signal, and the second radio frequency test signal has a center frequency higher than the center frequency of the outgoing radio-frequency communication signal;
wherein the incoming radio-frequency signal includes a first and a second radio-frequency test component caused by the respective first and second radio-frequency test signals;
wherein the demodulating includes demodulating the first and second radio-frequency test components to obtain respective first and second demodulated test components;
wherein the sampling includes sampling the first and second demodulated test component to obtain respective first and second sampled test components; and
wherein the processing includes processing of the first and second sampled test components to determine nonlinear distortion introduced by the power amplifier.
14. The method of claim 1, wherein the radio-frequency test signal includes a plurality of subcarrier signals, and wherein processing the sampled test component to determine nonlinear distortion includes processing the subcarrier signals to determine intermodulation distortion between the subcarrier signals.
15. The method of claim 1, wherein generating a combined radio-frequency communication signal includes:
combining an outgoing baseband communication signal with a sideband test signal to generate a combined baseband signal; and
modulating the combined sideband signal to radio frequency.