US 7,444,127 B2 · Methods and apparatus for selecting between multiple carriers using a receiver with multiple receiver chains

Abstract

Receivers accommodating frequency band selection methods in wireless communications systems are described. Different frequency bands are associated with different alternative carrier frequencies and/or base station cell and/or sector transmitter connection alternatives. Mobile node receivers include two receiver chains, each chain processing signals corresponding to a carrier. In some embodiments, each receiver chain includes its own controllable RF module, and individual carrier band selection is performed in each RF module. In some embodiments, the two receiver chains share a common RF module; however, each chain includes its own controllable baseband filter. In various embodiments, the first chain has higher complexity than the second chain. In most embodiments, each chain uses the same technology, e.g., spread spectrum OFDM or CDMA. Each chain obtains a quality indicator value on a different band and a comparison of quality indicator values is used in selecting the channel and carrier band for downlink traffic signaling.

Claims64

Dependent claims

A portable communications device comprising:

a first receiver chain including:
a first controllable filter;
a first decoder circuit coupled to said first controllable filter;
a signal quality detector;
and
a second receiver chain which is less complex than said first receiver chain and is implemented using fewer components than said first receiver chain, the second receiver chain including:
i) a second controllable filter;
and
ii) a first energy detection module coupled to said second controllable filter;
and
a band selection controller coupled to said signal quality detector, said energy detector, said first and second controllable filters, and said band selection controller selecting the frequency band of the first controllable filter as a function of a first signal quality indicator received from said signal quality detector, and a second signal quality indicator corresponding to an output of said energy detection circuit.

8 more elements

A method of operating a portable communications device comprising:

operating a first receiver chain to process a first signal, processing said first signal including:
i) performing a filtering operation on the first signal using a first controllable filter to generate a first filtered signal;
ii) performing a decoding operation on the first filtered signal using a first decoder circuit coupled to said first controllable filter;
and
iii) generating, using a signal quality detector, a first signal quality indicator used to indicate the quality of the first signal;
and
operating a second receiver chain which is less complex than said first receiver chain and is implemented using fewer components than said first receiver chain, to process a second signal, processing said second signal including:
i) performing a filtering operation on the second signal using a second controllable filter to generate a second filtered signal;
ii) generating an estimate of the energy of the second filtered signal using a first energy detection module;
and
iii) producing from the generated estimate of the energy a second signal quality indicator;
and
selecting the frequency band of the first controllable filter as a function of the first signal quality indicator and the second signal quality indicator.

10 more elements

A portable communications device comprising:

first receiver chain means for processing a first signal, said first receiver chain means including:
i) means for performing a filtering operation on the first signal using a first controllable filter to generate a first filtered signal;
ii) means for performing a decoding operation on the first filtered signal using a first decoder circuit coupled to said first controllable filter;
and
iii) means for generating, using a signal quality detector, a first signal quality indicator used to indicate the quality of the first signal;
and
second receiver chain means, which is less complex than said first receiver chain and is implemented using fewer components than said first receiver chain means, for processing a second signal, said second receiver chain means including:
i) means for performing a filtering operation on the second signal using a second controllable filter to generate a second filtered signal;
ii) means for generating an estimate of the energy of the second filtered signal using a first energy detection module;
and
iii) means for producing from the generated estimate of the energy a second signal quality indicator;
and
means for selecting the frequency band of the first controllable filter as a function of the first signal quality indicator and the second signal quality indicator.

10 more elements

A computer readable medium comprising:

stored instructions for controlling a first receiver chain to:
i) perform a filtering operation on a first signal using a first controllable filter to generate a first filtered signal;
ii) perform a decoding operation on the first filtered signal using a first decoder circuit coupled to said first controllable filter;
and
iii) generate, using a signal quality detector, a first signal quality indicator used to indicate the quality of the first signal;
and
stored instructions for controlling a second receiver chain which is less complex than said first receiver chain and is implemented using fewer components than said first receiver chain, to:
i) perform a filtering operation on the second signal using a second controllable filter to generate a second filtered signal;
ii) generate an estimate of the energy of the second filtered signal using a first energy detection module;
and
iii) produce from the generated estimate of the energy a second signal quality indicator;
and
stored instructions for controlling a module to select the frequency band of the first controllable filter as a function of the first signal quality indicator and the second signal quality indicator.

10 more elements

A processor comprising:

a first receiver chain configured to:
i) perform a filtering operation on a first signal using a first controllable filter to generate a first filtered signal;
ii) perform a decoding operation on the first filtered signal using a first decoder circuit coupled to said first controllable filter;
and
iii) generate, using a signal quality detector, a first signal quality indicator used to indicate the quality of the first signal;
and
a second receiver chain which is less complex than said first receiver chain and is implemented using fewer components than said first receiver chain, the second receiver chain being configured to:
i) perform a filtering operation on the second signal using a second controllable filter to generate a second filtered signal;
ii) generate an estimate of the energy of the second filtered signal using a first energy detection module;
and
iii) produce from the generated estimate of the energy a second signal quality indicator;
and
a control module configured to select the frequency band of the first controllable filter as a function of the first signal quality indicator and the second signal quality indicator.

10 more elements

Dependencies are inferred from the claim text.

Methods and apparatus for selecting between multiple carriers using a receiver with multiple receiver chains

Life of this patent

Methods and apparatus for selecting between multiple carriers using a receiver with multiple receiver chains

Life of this patent

Abstract

Claims64