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Researchers Submit Patent Application, "Apparatus and Methods for Signal Reception Based on Network Load Estimations", for Approval

February 20, 2014



By a News Reporter-Staff News Editor at Politics & Government Week -- From Washington, D.C., VerticalNews journalists report that a patent application by the inventors SEBENI, Johnson (Cupertino, CA); WANG, Yu-Lin (Cupertino, CA); SHI, Jianxiong (1 Infinite Loop, CA), filed on September 27, 2013, was made available online on February 6, 2014.

The patent's assignee is Apple Inc.

News editors obtained the following quote from the background information supplied by the inventors: "The present invention relates generally to the field of wireless communication and data networks. More particularly, in one exemplary aspect, the present invention is directed to methods and apparatus for adjusting signal reception based on estimations of network load.

"In telecommunications networks, 'orthogonality' refers to systems, processes, signaling, effects, etc. which exhibit desirable exclusionary properties. Orthogonal properties are heavily leveraged in multiple access communication schemes. Consider an aggregate signal composed of several orthogonal constituent signals. Ideally, a receiver can extract a desired signal from the aggregate signal, and reject the other orthogonal constituent signals. In this example, each of the orthogonal constituent signals is removable 'interference'.

"For example, CDMA (Code Division Multiple Access) based systems utilize a complex series of orthogonal 'spreading codes' to distinguish between each data and control channel. A CDMA signal can be separated into its constituent channels, ideally without interference between the constituent channels (i.e., inter-channel interference or ICI).

"In contrast to unwanted orthogonal signaling, true noise is 'non-orthogonal' and does not exhibit simple exclusionary properties. For example, true noise includes elements such as nearby interfering systems, thermal noise, transmission effects, etc. Unlike orthogonal signaling, true noise is largely unpredictable and cannot be removed. Generally, true noise must be corrected using error correction techniques, or rendered insignificant to the transmitted signal power.

"In typical wireless reception, an RF frontend 'conditions' and converts a received RF waveform to a digital representation for subsequent demodulation and/or processing. Most designs for RF frontends implement signal conditioning stages before demodulation and/or processing stages. Also, RF frontends are typically constructed around fixed point arithmetic for cost and simplicity reasons (i.e., a fixed number of digits are used for operations).

"Unfortunately, practical design constraints can create artifacts in normal operation. For example, in low noise environments, unwanted orthogonal signals can have much higher transmission power than the desired signal. These unwanted orthogonal signals will dominate the signal conditioning operations. As described in greater detail subsequently herein, such conditions can occur when a mobile device is very close to a sparsely unoccupied base station (or femtocell). Once the unwanted orthogonal signals (such as pilot channels, broadcast channels, etc.) have been removed, the desired signal is significantly under-powered, which can create quantization error effects in fixed point circuitry. Quantization errors can lead to much higher bit error rates (BERs).

"Therefore, improved methods and apparatus are needed for handling scenarios where large differences are observed between known interference and desired signals. Such improved methods and apparatus should ideally facilitate successful decoding of signals, regardless of the current cellular conditions. Specifically, new solutions are needed for preserving cellular network performance, in low-noise, high-interference rejection environments.

"Furthermore, it is additionally recognized that corresponding improvements are needed to existing hardware. Ideally, implementation of the aforementioned improved methods and apparatus should not require substantial changes to extant transceiver hardware or software. The non-ideal behaviors of hardware-specific implementations should be accounted for in signal conditioning, demodulation, post-processing, etc."

As a supplement to the background information on this patent application, VerticalNews correspondents also obtained the inventors' summary information for this patent application: "The present invention satisfies the foregoing needs by providing, inter alia, improved methods and apparatus for adjusting signal reception based on one or more estimations of network load.

"In a first aspect of the present invention, a method for improving quantization rejection of at least one signal among a plurality of signals and noise is disclosed. In one embodiment, the plurality of signals includes at least one other known signal and the method includes: transmitting the plurality of signals; receiving information related to an estimated network load based on a measured first attribute; and adjusting the transmission characteristics of at least one but not all of the plurality of signals based on the information.

"In one variant, the first attribute comprises a ratio of a first parameter of the network to a second parameter of the network. The first parameter of the network comprises e.g., a common channel power, and the second parameter of the network comprises a total received signal. The network is compliant with the Universal Mobile Telecommunications System (UMTS) standard(s), and the common channel comprises a common pilot channel (CPICH).

"In another variant, the method includes comparing the received information to at least one criterion; and based at least in part on the result of the comparing, selectively performing the transmission characteristics.

"In a further variant, the act of adjusting the transmission characteristics includes signal amplification.

"In yet another variant, the act of adjusting the transmission characteristics includes lowering the constellation order.

"In another variant, the act of adjusting the transmission characteristics includes changing the transmission rate.

"In still another variant, the act of adjusting the transmission characteristics includes changing one or more feedback parameters.

"In a second aspect of the present invention, a method for enhancing the quantization performance of at least one radio signal among a plurality of radio signals is disclosed. In one embodiment, the method includes: transmitting the plurality of radio signals, the transmission having a first radio attribute; receiving information related to a network load based on the first attribute; and adjusting the transmission characteristics of at least one of the plurality of signals based on the information.

"In one variant, the network is compliant with the Universal Mobile Telecommunications System (UMTS) standard(s), and the first radio attribute comprises a ratio of a common channel power to a total received signal.

"In another variant, the act of generating comprises: comparing the ratio to at least one threshold criterion; and based at least in part on the result of the comparing, selectively performing the adjusting of the transmission characteristics.

"In still another variant, the at least one radio signal is a dedicated channel.

"In a further variant, the plurality of radio signals includes at least one common signal, at least one unwanted signal, and at least one wanted signal In one variant, the act of adjusting the transmission characteristics includes signal amplification of the at least one wanted signal. In another variant, the act of adjusting the transmission characteristics includes lowering the constellation order of the at least one wanted signal. In yet another variant, the act of adjusting the transmission characteristics includes changing the transmission rate of the at least one wanted signal. In yet another variant, act of adjusting the transmission characteristics includes changing one or more feedback parameters of the at least one wanted signal.

"In a third aspect of the invention, a wireless apparatus is disclosed. In one embodiment, the wireless apparatus includes: a wireless interface, the wireless interface adapted to receive a plurality of signals; logic adapted to determine a network load; a processing device coupled to a memory; and a computer program comprising a plurality of executable instructions resident within the memory. When executed by the processing device, the program: receives a first signaling channel via the wireless interface; requests a second signaling channel; estimates the network load; and transmits information relating to the estimated network load. One or more reception characteristics of the second signaling channel are determined by the information.

"In one variant, the wireless interface has multiple fixed point capabilities, and the fixed point capability is a reception characteristic determined by the information.

"In another variant, the reception characteristic is a target signal to interference (SIR) level.

"In yet another variant, the reception characteristic is negotiated with a serving device.

"In still another variant, the information relating to the estimated network load comprises an indication of the first signal channel strength, relative to the plurality of signals strength.

"In a fourth aspect of the present invention, a serving apparatus is disclosed. In one embodiment, the apparatus comprises: a wireless interface, the wireless interface adapted to transmit and receive a plurality of signals; a processing device coupled to a memory; and a computer program plurality of executable instructions resident within the memory. When executed by the processing device, the program: receives a network load estimation via the wireless interface; and responsively adjusts one or more transmission characteristics of at least one, but not all, of the plurality of signals.

"In a fifth aspect of the invention, a method for compensating for one or more orthogonal signals having much higher transmission power than a user signal is disclosed. In one embodiment, the orthogonal signals result in quantization error in the user signal, and the method comprising: obtaining a network load estimation; and responsively adjusting one or more transmission characteristics of the user signal based at least in part on the network load, the adjusting mitigating the quantization error.

"In one variant one or more orthogonal signals comprises a pilot channel, and the adjusting the one or more transmission characteristics of the user signal comprises increasing the transmission power of the user signal.

"In a sixth aspect of the invention, a wireless system is disclosed. In one embodiment, the system includes a base station and at least one user device (e.g., mobile device or UE), and the system is adapted to dynamically adjust for quantization errors induced by the noise environment and system parameters by adjusting one or more channel characteristics.

"Other features and advantages of the present invention will immediately be recognized by persons of ordinary skill in the art with reference to the attached drawings and detailed description of exemplary embodiments as given below.

BRIEF DESCRIPTION OF THE DRAWINGS

"FIG. 1 is a graphical illustration of one embodiment of a prior art Universal Mobile Telecommunications System (UMTS) network comprising a Core Network, a plurality of Base Stations, and a plurality of User Equipment.

"FIG. 2 is a prior art graphical illustration of Automatic Gain Control (AGC) and Analog-to-Digital Conversion (A/D) methods emphasizing the effects of proper and improper AGC and A/D operation.

"FIG. 3 is a graphical representation of one approach for Received Signal Strength (RSS) calculation useful in conjunction with the AGC calculation of various embodiments of the invention.

"FIG. 4 is a logical representation of one exemplary Automatic Gain Control (AGC) feedback loop useful in conjunction with the present invention.

"FIG. 5 is a graphical representation of a signal composition adapted to improve quantization noise in accordance with one exemplary embodiment of the present invention.

"FIG. 6 is a logical flow diagram of an exemplary embodiment of the generalized process for improving signal reception based on one or more estimations of network load, in accordance with the present invention.

"FIG. 7 is a logical flow diagram illustrating one exemplary implementation of the method of FIG. 6.

"FIG. 8 is a block diagram of one embodiment of a generalized serving apparatus configured in accordance with the present invention.

"FIG. 9 is a block diagram of one embodiment of a generalized receiving apparatus configured in accordance with the present invention.

"FIG. 10 is time and frequency representation of an Orthogonal Frequency Division Multiple Access (OFDMA) implementation useful in conjunction with various embodiments of the invention."

For additional information on this patent application, see: SEBENI, Johnson; WANG, Yu-Lin; SHI, Jianxiong. Apparatus and Methods for Signal Reception Based on Network Load Estimations. Filed September 27, 2013 and posted February 6, 2014. Patent URL: http://appft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.html&r=3924&p=79&f=G&l=50&d=PG01&S1=20140130.PD.&OS=PD/20140130&RS=PD/20140130

Keywords for this news article include: Apple Inc., Telecommunications.

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Source: Politics & Government Week


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