Global navigation satellite system receiver with filter bypass mode for improved sensitivity

An apparatus comprising:

• means for providing a non-bypass signal path to a receiver configured to receive positioning signals from a Global Navigation Satellite Systems (GNSS), the non-bypass signal path comprising a means for filtering;
• means for providing a bypass signal path to the receiver, the bypass signal path configured to bypass the filter, the means for providing the bypass signal path comprising means for providing at least one input matching network (IMN), the means for providing the at least one IMN configured to provide impedance matching and filtering and to provide a broader pass band than the means for filtering of the non-bypass signal path, the means for providing the at least one IMN further comprising a second filtering means and a third filtering means, the second filtering means comprising means for attenuating a first range of frequencies used for transmitting signals unrelated to the positioning signals and associated with at least one non-local transmitter using a first notch filter, the third filtering means comprising means for attenuating a second range of frequencies used for transmitting signals unrelated to the positioning signals and associated with another at least one non-local transmitter using a second notch filter, wherein the presence of signals within both the first range of frequencies and the second range of frequencies produce second order distortions within a third frequency range associated with the positioning signals which the receiver is configured to receive;
• first processing means for generating a control signal for alternatively routing the received signal through either the non-bypass signal path or the bypass signal path based on whether an expected signal power for transmission signals in the first range of frequencies or the second range of frequencies by an unrelated local transmitter exceeds a selected threshold;
• delay compensation means comprising a second processing means and a data storage means, the second processing means being configured to access time delay information stored in the data storage means and being further configured to select first delay information from the data storage means to compensate for a first time delay associated with the non-bypass signal path responsive to the control signal from the first processing means indicating that the non-bypass signal path has been selected and to select second delay information from the data storage means to compensate for a second time delay associated with the bypass signal path responsive to the control signal from the first processing means indicating that the bypass signal path has been selected, wherein the delay compensation means is configured to provide the selected first delay information or second delay information to the first processing means, and wherein first processing means, during signal processing for positioning signal determination, is configured to use the first delay information to compensate for delays associated with the non-bypass signal path and to use the second delay information to compensate for delays associated with the bypass-signal path;
• and
• means for switching configured to receive the control signal and in response thereto to select the non-bypass path when the expected signal power exceeds the selected threshold and select the bypass path when the expected signal power does not exceed the selected threshold.

A method comprising:

• generating, using a first processor, a control signal for alternatively routing a received signal through either a non-bypass signal path or a bypass signal path based on whether the expected signal power for transmission signals by the unrelated local transmitter exceeds a selected threshold, wherein the unrelated local transmitter is unrelated to a local receiver configured to receive positioning signals from a Global Navigation Satellite Systems (GNSS);
• switching based on the control signal and in response thereto selecting the non-bypass path when the expected signal power exceeds the selected threshold and selecting the bypass path when the expected signal power does not exceed the selected threshold;
• matching an impedance of using an input matching network (IMN) and filtering, the IMN comprising a first notch filter configured to attenuate a first range of frequencies used for transmitting signals unrelated to the positioning signals and associated with at least one non-local transmitter and a second notch filter configured to attenuate a second range of frequencies used for transmitting signals unrelated to the positioning signals and associated with another at least one non-local transmitter, wherein the presence of signals within both the first range of frequencies and the second range of frequencies produce second order distortions within a third frequency range at which the receiver is configured to receive a signal, the IMN providing a broader pass band than a filter of the non-bypass signal path;
• obtaining time delay information from a delay compensator comprising a second processor and a memory, wherein obtaining the time delay information further comprises accessing the time delay information stored in the memory with the second processor, and selecting first delay information from the memory to compensate for a first time delay associated with the non-bypass signal path responsive to the control signal indicating that the non-bypass signal path has been selected, and selecting second delay information from the memory to compensate for a second time delay associated with the bypass signal path responsive to the control signal indicating that the bypass signal path has been selected,
• compensating for the first time delay or the second time delay, during signal processing for positioning signal determination, using the first delay information to compensate for delays associated with the non-bypass signal path or the second delay information to compensate for delays associated with the bypass-signal path;
• attenuating a range of frequencies associated with at least one non-local transmitter and the another at least one non-local transmitter.