# US 6,169,728 A · Apparatus and method for spectrum management in a multipoint communication system

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- Number: US 6,169,728 A
- Document ID: US6169728A
- Status: Granted
- Kind: A
- Application number: 08/929,008
- Filed: 1997-09-08
- Granted: 2001-01-02
- Earliest claimed: 1996-03-29
- Assignees: Motorola, Inc.
- Inventors: John A. Perreault; Dennis J. Picker; Sunil K. Menon
- Web page: https://patentgrep.com/patent/US6169728A

## CPC

- H04N 7/17309: {Transmission or handling of upstream communications}
- H04H 20/42: Arrangements for resource management
- H04H 20/78: CATV [Community Antenna Television] systems
- H04J 1/12: Arrangements for reducing cross-talk between channels {(in line transmission systems H04B3/32; in cables or lines H04B3/26 - H04B3/30)}
- H04N 21/6473: {Monitoring network processes errors (for recovering from a failure of a protocol instance or entity H04L69/40)}
- H04N 21/64738: {Monitoring network characteristics, e.g. bandwidth, congestion level (data switched network analysis H04L41/14; monitoring functioning in data switched networks H04L43/0817; flow control in packet networks H04L47/10)}
- H04N 21/64753: {directed to the client}
- H04N 21/64761: {directed to the server}
- H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04H: BROADCAST COMMUNICATION (multiplex communication H04J; pictorial communication aspects of broadcast systems H04N)
- H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S)

## Abstract

The apparatus (101) and method for spectrum management in a multipoint communication system controls upstream channel usage for secondary stations (110) transmitting information to a primary station (101) and downstream channel usage for secondary stations (110) receiving information from a primary station (101). The preferred apparatus (101) embodiment includes a processor arrangement (120) having a master controller (121) and a plurality of processors (130), with the processor arrangement connected to a channel interface (125). The apparatus (101) and method controls channel load balancing, channel congestion, and channel assignment in a multipoint communication system, and controls upstream channels independently from downstream channels. Factors and parameters utilized in such channel control and allocation include error parameters, channel noise parameters, transmit and receive loading factors, and congestion parameters.

## Claims

### Claim 1

A method for spectrum management in a communication system, the communication system having a communication medium, the communication medium having a plurality of downstream communication channels, the communication medium further having a plurality of upstream communication channels, the communication system further having a plurality of secondary stations coupleable to the communication medium, each secondary station of the plurality of secondary stations having a receiver and a transmitter, the method comprising:
(a) allocating loading of the plurality of upstream communication channels and of the plurality of downstream communication channels for an entering secondary station of the plurality of secondary stations;
(b) allocating loading of the plurality of upstream communication channels and of the plurality of downstream communication channels for an active secondary station of the plurality of secondary stations;
(c) allocating the plurality of upstream communication channels and the plurality of downstream communication channels based upon an error parameter; and
(d) allocating loading of the plurality of upstream communication channels and of the plurality of downstream communication channels based upon a congestion parameter.

### Claim 2 (depends on 1)

The method of claim 1, further comprising:
(e) repeating steps (a) through (d), inclusive.

### Claim 3 (depends on 1)

The method of claim 1 wherein step (c) further comprises:
(c1) monitoring an error rate for each upstream communication channel of the plurality of upstream communication channels;
(c2) determining whether the error rate for each upstream communication channel of the plurality of upstream communication channels exceeds a first threshold to form a set of upstream high error channels;
(c3) determining a channel noise parameter for a first upstream high error channel of the set of upstream high error channels;
(c4) when the channel noise parameter of the first upstream high error channel exceeds a second threshold, transferring a secondary station transmitter from the first upstream high error channel to a first idle upstream communication channel of the plurality of upstream communication channels, the first idle upstream communication channel then having a channel noise parameter lower than the second threshold; and
(c5) when the channel noise parameter of the first upstream high error channel is less than the second threshold, transferring a secondary station transmitter from the first upstream high error channel to a second idle upstream communication channel of the plurality of upstream communication channels, the second idle upstream communication channel having a frequency higher than a frequency of the first upstream high error channel.

### Claim 4 (depends on 3)

The method of claim 3, further comprising:
(c6) repeating steps (c3) through (c5), inclusive, for each high error channel of the plurality of high error channels.

### Claim 5 (depends on 3)

The method of claim 3, further comprising:
(c7) repeating steps (c1) through (c6), inclusive.

### Claim 6 (depends on 3)

The method of claim 3 wherein the first threshold and the second threshold are predetermined.

### Claim 7 (depends on 3)

The method of claim 3 wherein the first threshold and the second threshold are adaptive.

### Claim 8 (depends on 3)

The method of claim 3, wherein the channel noise parameter is the received signal strength measured when an upstream high error channel of the set of upstream high error channels is idle.

### Claim 9 (depends on 1)

The method of claim 1 wherein step (c) further comprises:
(c8) monitoring a downstream error rate for each secondary station of the plurality of secondary stations which is connected to a first downstream communication channel of the plurality of downstream communication channels; and
(c9) when a predetermined number of the plurality of secondary stations have a downstream error rate which exceeds a threshold, transferring a secondary station receiver from the first downstream communication channel to a second downstream communication channel of the plurality of downstream communication channels.

### Claim 10 (depends on 9)

The method of claim 9 wherein the third threshold is predetermined.

### Claim 11 (depends on 9)

The method of claim 9 wherein the third threshold is adaptive.

### Claim 12 (depends on 1)

The method of claim 1 wherein step (a) further comprises:
(a1) determining a receive loading factor for each receiver of a plurality of primary station receivers to form a plurality of receive loading factors;
(a2) when the plurality of receive loading factors indicate initialization of the communication system, sequentially assigning a transmitter of each secondary station of the plurality of secondary stations to each receiver of the plurality of primary station receivers; and
(a3) when the plurality of receive loading factors do not indicate initialization of the communication system, assigning a transmitter of an entering secondary station of the plurality of secondary stations to a receiver of the plurality of primary station receivers then having a lowest receive loading factor.

### Claim 13 (depends on 1)

The method of claim 1 wherein step (a) further comprises:
(a4) determining a transmit loading factor for each transmitter of a plurality of primary station transmitters to form a plurality of transmit loading factors;
(a5) when the plurality of transmit loading factors indicate initialization of the communication system, sequentially assigning a receiver of each secondary station of the plurality of secondary stations to each transmitter of the plurality of primary station transmitters; and
(a6) when the plurality of transmit loading factors do not indicate initialization of the communication system, assigning a receiver of an entering secondary station of the plurality of secondary stations to a transmitter of the plurality of primary station transmitters then having a lowest transmit loading factor.

### Claim 14 (depends on 1)

The method of claim 1 wherein step (b) further comprises:
(b1) determining a receive loading factor for each receiver of a plurality of primary station receivers to form a plurality of receive loading factors;
(b2) when a variation of the plurality of receive loading factors exceeds a threshold, selecting a first receiver of the plurality of primary station receivers then having a highest receive loading factor;
(b3) for the first receiver, determining an impact level of a transfer for each corresponding secondary station transmitter of the plurality of secondary stations and selecting a secondary station transmitter of the plurality of secondary stations then having a highest impact level to form a selected transmitter;
(b4) selecting a second receiver of the plurality of primary station receivers then having a receive loading factor less than a mean receive loading factor and determining a second receive loading factor for the selected receiver in conjunction with the selected transmitter; and
(b5) when the second receive loading factor is less than the mean receive loading factor, transferring the selected transmitter to the second receiver.

### Claim 15 (depends on 14)

The method of claim 14, wherein step (b3) further comprises:
(b3i) determining whether communication system historical information precludes a potential transfer of the selected transmitter; and
(b3ii) when communication system historical information precludes the potential transfer of the selected transmitter, selecting a secondary station transmitter of the plurality of secondary stations then having a next highest impact level to form the selected transmitter.

### Claim 16 (depends on 14)

The method of claim 14, wherein step (b3) further comprises:
(b3iii) determining whether communication system protocol information precludes a potential transfer of the selected transmitter; and
(b3iv) when communication system protocol information precludes the potential transfer of the selected transmitter, selecting a secondary station transmitter of the plurality of secondary stations then having a next highest impact level to form the selected transmitter.

### Claim 17 (depends on 14)

The method of claim 14 wherein the threshold is predetermined.

### Claim 18 (depends on 14)

The method of claim 14 wherein the threshold is adaptive.

### Claim 19 (depends on 14)

The method of claim 14 wherein the receive loading factor further comprises a weighted combination of a packet rate, a bit rate, and a cycle time.

### Claim 20 (depends on 1)

The method of claim 1 wherein step (b) further comprises:
(b6) determining a transmit loading factor for each transmitter of a plurality of primary station transmitters to form a plurality of transmit loading factors;
(b7) when a variation of the plurality of transmit loading factors exceeds a threshold, selecting a first transmitter of the plurality of primary station transmitters then having a highest transmit loading factor;
(b8) for the first transmitter, determining an impact level of a transfer for each corresponding secondary station receiver of the plurality of secondary stations and selecting a secondary station receiver of the plurality of secondary stations then having a highest impact level to form a selected receiver;
(b9) selecting a second transmitter of the plurality of primary station transmitters then having a transmit loading factor less than a mean transmit loading factor and determining a second transmit loading factor for the second transmitter in conjunction with the selected receiver; and
(b10) when the second transmit loading factor is less than the mean transmit loading factor, transferring the selected receiver to the second transmitter.

### Claim 21 (depends on 20)

The method of claim 20, wherein step (b8) further comprises:
(b8i) determining whether communication system historical information precludes a potential transfer of the selected receiver; and
(b8ii) when communication system historical information precludes the potential transfer of the selected receiver, selecting a secondary station receiver of the plurality of secondary stations then having a next highest impact level to form the selected receiver.

### Claim 22 (depends on 20)

The method of claim 20, wherein step (b8) further comprises:
(b8iii) determining whether communication system protocol information precludes a potential transfer of the selected receiver; and
(b8iv) when communication system protocol information precludes the potential transfer of the selected receiver, selecting a secondary station receiver of the plurality of secondary stations then having a next highest impact level to form the selected receiver.

### Claim 23 (depends on 20)

The method of claim 20 wherein the threshold is predetermined.

### Claim 24 (depends on 20)

The method of claim 20 wherein the threshold is adaptive.

### Claim 25 (depends on 20)

The method of claim 20 wherein the transmit loading factor further comprises a weighted combination of a packet rate, a bit rate, and a queue depth.

### Claim 26 (depends on 1)

The method of claim 1 wherein step (d) further comprises:
(d1) determining a congestion parameter for each receiver of a plurality of primary station receivers to form a plurality of congestion parameters;
(d2) when a congestion parameter of the plurality of congestion parameters exceeds a first threshold, selecting a first receiver of the plurality of primary station receivers then having a highest congestion parameter;
(d3) for the first receiver, determining an impact level of a transfer for each corresponding secondary station transmitter of the plurality of secondary stations and selecting a secondary station transmitter of the plurality of secondary stations then having a highest impact level to form a selected transmitter;
(d4) selecting a second receiver of the plurality of primary station receivers then having a congestion parameter less than the first threshold and determining a second congestion parameter for the second receiver in conjunction with the selected transmitter; and
(d5) when the second congestion parameter is less than the first threshold, transferring the selected transmitter to the second receiver.

### Claim 27 (depends on 26)

The method of claim 26, wherein step (d3) further comprises:
(d3i) determining whether communication system historical information precludes a potential transfer of the selected transmitter; and
(d3ii) when communication system historical information precludes the potential transfer of the selected transmitter, selecting a secondary station transmitter of the plurality of secondary stations then having a next highest impact level to form the selected transmitter.

### Claim 28 (depends on 26)

The method of claim 26, wherein step (d3) further comprises:
(d3iii) determining whether communication system protocol information precludes a potential transfer of the selected transmitter; and
(d3iv) when communication system protocol information precludes the potential transfer of the selected transmitter, selecting a secondary station transmitter of the plurality of secondary stations then having a next highest impact level to form the selected transmitter.

### Claim 29 (depends on 26)

The method of claim 26, further comprising:
(d6) repeating steps (d3) through (d5), inclusive, until the congestion parameter of the first receiver has decreased below a hysteresis threshold.

### Claim 30 (depends on 29)

The method of claim 29 wherein the first threshold and the hysteresis threshold are predetermined.

### Claim 31 (depends on 29)

The method of claim 29 wherein the first threshold and the hysteresis threshold are adaptive.

### Claim 32 (depends on 26)

The method of claim 26 wherein the congestion parameter is an access latency factor.

### Claim 33 (depends on 1)

The method of claim 1 wherein step (d) further comprises:
(d6) determining a congestion parameter for each transmitter of a plurality of primary station transmitters to form a plurality of congestion parameters;
(d7) when a congestion parameter of the plurality of congestion parameters exceeds a first threshold, selecting a first transmitter of the plurality of primary station transmitters then having a highest congestion parameter;
(d8) for the first transmitter, determining an impact level of a transfer for each corresponding secondary station receiver of the plurality of secondary stations and selecting a secondary station receiver of the plurality of secondary stations then having a highest impact level to form a selected receiver;
(d9) selecting a second transmitter of the plurality of primary station transmitters then having a congestion parameter less than the first threshold and determining a second congestion parameter for the second transmitter in conjunction with the selected receiver; and
(d10) when the second congestion parameter is less than first threshold, transferring the selected receiver to the second transmitter.

### Claim 34 (depends on 33)

The method of claim 33, wherein step (d8) further comprises:
(d8i) determining whether communication system historical information precludes a potential transfer of the selected receiver; and
(d8ii) when communication system historical information precludes the potential transfer of the selected receiver, selecting a secondary station receiver of the plurality of secondary stations then having a next highest impact level to form the selected receiver.

### Claim 35 (depends on 33)

The method of claim 33, wherein step (d8) further comprises:
(d8iii) determining whether communication system protocol information precludes a potential transfer of the selected receiver; and
(d8iv) when communication system protocol information precludes the potential transfer of the selected receiver, selecting a secondary station receiver of the plurality of secondary stations then having a next highest impact level to form the selected receiver.

### Claim 36 (depends on 33)

The method of claim 33, further comprising:
(d11) repeating steps (d8) through (d10), inclusive, until the congestion parameter of the first transmitter has decreased below a hysteresis threshold.

### Claim 37 (depends on 36)

The method of claim 36 wherein the first threshold and the hysteresis threshold are predetermined.

### Claim 38 (depends on 36)

The method of claim 36 wherein the first threshold and the hysteresis threshold are adaptive.

### Claim 39 (depends on 33)

The method of claim 33 wherein the congestion parameter is a throughput factor.

### Claim 40

An apparatus for spectrum management in a communication system, the communication system having a communication medium, the communication medium having a plurality of downstream communication channels, the communication medium further having a plurality of upstream communication channels, the communication system further having a plurality of secondary stations coupleable to the communication medium, each secondary station of the plurality of secondary stations having a receiver and a transmitter, the apparatus comprising:
a channel interface coupleable to the communication medium for signal transmission on a downstream communication channel of the plurality of downstream communication channels and for signal reception on an upstream communication channel of the plurality of upstream communication channels; and
a processor arrangement coupled to the channel interface, the processor arrangement responsive through a set of program instructions to allocate loading of the plurality of upstream communication channels and of the plurality of downstream communication channels for an entering secondary station of the plurality of secondary stations; to allocate loading of the plurality of upstream communication channels and of the plurality of downstream communication channels for an active secondary station of the plurality of secondary stations; to allocate the plurality of upstream communication channels and the plurality of downstream communication channels based upon an error parameter; and to allocate loading of the plurality of upstream communication channels and of the plurality of downstream communication channels based upon a congestion parameter.

### Claim 41 (depends on 40)

The apparatus of claim 40 wherein the processor arrangement is further responsive:
to monitor an error rate for each upstream communication channel of the plurality of upstream communication channels; to determine whether the error rate for each upstream communication channel of the plurality of upstream communication channels exceeds a first threshold to form a set of upstream high error channels;
to determine a channel noise parameter for a first upstream high error channel of the set of upstream high error channels;
when the channel noise parameter of the first upstream high error channel exceeds a second threshold, to transfer a secondary station transmitter from the first upstream high error channel to a first idle upstream communication channel of the plurality of upstream communication channels, the first idle upstream communication channel then having a channel noise parameter lower than the second threshold; and
when the channel noise parameter of the first upstream high error channel is less than the second threshold, to transfer a secondary station transmitter from the first upstream high error channel to a second idle upstream communication channel of the plurality of upstream communication channels, the second idle upstream communication channel having a frequency higher than a frequency of the first upstream high error channel.

### Claim 42 (depends on 41)

The apparatus of claim 41 wherein the first threshold and the second threshold are predetermined.

### Claim 43 (depends on 41)

The apparatus of claim 41 wherein the first threshold and the second threshold are adaptive.

### Claim 44 (depends on 41)

The apparatus of claim 41, wherein the channel noise parameter is the received signal strength measured when a high error channel of the plurality of high error channels is idle.

### Claim 45 (depends on 40)

The apparatus of claim 40 wherein the processor arrangement is further responsive:
to monitor a downstream error rate for each secondary station connected to a first downstream communication channel of the plurality of downstream communication channels; and
when a predetermined number of the plurality of secondary stations have a downstream error rate which exceeds a threshold, to transfer a secondary station receiver from the first downstream communication channel to a second downstream communication channel of the plurality of downstream communication channels.

### Claim 46 (depends on 45)

The apparatus of claim 45 wherein the threshold is predetermined.

### Claim 47 (depends on 45)

The apparatus of claim 45 wherein the threshold is adaptive.

### Claim 48 (depends on 40)

The apparatus of claim 40 wherein the processor arrangement is further responsive:
to determine a receive loading factor for each receiver of a plurality of primary station receivers to form a plurality of receive loading factors;
when the plurality of receive loading factors indicate initialization of the communication system, to sequentially assign a transmitter of each secondary station transmitter of the plurality of secondary stations to each receiver of the plurality of primary station receivers; and
when the plurality of receive loading factors do not indicate initialization of the communication system, to assign a transmitter of an entering secondary station of the plurality of secondary stations to a receiver of the plurality of primary station receivers then having a lowest receive loading factor.

### Claim 49 (depends on 40)

The apparatus of claim 40 wherein the processor arrangement is further responsive:
to determine a transmit loading factor for each transmitter of a plurality of primary station transmitters to form a plurality of transmit loading factors;
when the plurality of transmit loading factors indicate initialization of the communication system, to sequentially assign a receiver of each secondary station of the plurality of secondary stations to each transmitter of the plurality of primary station transmitters; and
when the plurality of transmit loading factors do not indicate initialization of the communication system, to assign a receiver of an entering secondary station of the plurality of secondary stations to a transmitter of the plurality of primary station transmitters then having a lowest transmit loading factor.

### Claim 50 (depends on 40)

The apparatus of claim 40 wherein the processor arrangement is further responsive:
to determine a receive loading factor for each receiver of a plurality of primary station receivers to form a plurality of receive loading factors;
when a variation of the plurality of receive loading factors exceeds a threshold, to select a first receiver of the plurality of primary station receivers then having a highest receive loading factor;
for the first receiver, to determine an impact level of a transfer for each corresponding secondary station transmitter of the plurality of secondary stations and selecting a secondary station transmitter of the plurality of secondary stations then having a highest impact level to form a selected transmitter;
to select a second receiver of the plurality of primary station receivers then having a receive loading factor less than a mean receive loading factor and to determine a second receive loading factor for the second receiver in conjunction with the selected transmitter; and
when the second receive loading factor is less than the mean receive loading factor, to transfer the selected transmitter to the second receiver.

### Claim 51 (depends on 50)

The apparatus of claim 50, wherein the processor arrangement is further responsive:
to determine whether communication system historical information precludes a potential transfer of the selected transmitter; and
when communication system historical information precludes the potential transfer of the selected transmitter, to select a secondary station transmitter of the plurality of secondary stations then having a next highest impact level to form the selected transmitter.

### Claim 52 (depends on 50)

The apparatus of claim 50, wherein the processor arrangement is further responsive to:
to determine whether communication system protocol information precludes a potential transfer of the selected transmitter; and
when communication system protocol information precludes the potential transfer of the selected transmitter, to select a secondary station transmitter of the plurality of secondary stations then having a next highest impact level to form the selected transmitter.

### Claim 53 (depends on 50)

The apparatus of claim 50 wherein the threshold is predetermined.

### Claim 54 (depends on 50)

The apparatus of claim 50 wherein the threshold is adaptive.

### Claim 55 (depends on 50)

The apparatus of claim 50 wherein the receive loading factor further comprises a weighted combination of a packet rate, a bit rate, and a cycle time.

### Claim 56 (depends on 40)

The apparatus of claim 40 wherein the processor arrangement is further responsive:
to determine a transmit loading factor for each transmitter of a plurality of primary station transmitters to form a plurality of transmit loading factors;
when a variation of the plurality of transmit loading factors exceeds a threshold, to select a first transmitter of the plurality of primary station transmitters then having a highest transmit loading factor;
for the first transmitter, to determine an impact level of a transfer for each corresponding secondary station receiver of the plurality of secondary stations and to select the secondary station receiver of the plurality of secondary stations then having a highest impact level to form a selected receiver;
to select a second transmitter of the plurality of primary station transmitters then having a transmit loading factor less than a mean transmit loading factor and to determine a second transmit loading factor for the selected transmitter in conjunction with the second receiver; and
when the second transmit loading factor is less than the mean transmit loading factor, to transfer the selected receiver to the second transmitter.

### Claim 57 (depends on 56)

The apparatus of claim 56, wherein the processor arrangement is further responsive:
to determine whether communication system historical information precludes a potential transfer of the selected receiver; and
when communication system historical information precludes the potential transfer of the selected receiver, to select a secondary station receiver of the plurality of secondary stations then having a next highest impact level to form the selected receiver.

### Claim 58 (depends on 56)

The apparatus of claim 56, wherein the processor arrangement is further responsive:
to determine whether communication system protocol information precludes a potential transfer of the selected receiver; and
when communication system protocol information precludes the potential transfer of the selected receiver, to select a secondary station receiver of the plurality of secondary stations then having a next highest impact level to form the selected receiver.

### Claim 59 (depends on 56)

The apparatus of claim 56 wherein the threshold is predetermined.

### Claim 60 (depends on 56)

The apparatus of claim 56 wherein the threshold is adaptive.

### Claim 61 (depends on 56)

The apparatus of claim 56 wherein the transmit loading factor further comprises a weighted combination of a packet rate, a bit rate, and a queue depth.

### Claim 62 (depends on 40)

The apparatus of claim 40 wherein the processor arrangement is further responsive:
to determine a congestion parameter for each receiver of a plurality of primary station receivers to form a plurality of congestion parameters;
when a congestion parameter of the plurality of congestion parameters exceeds a first threshold, to select a first receiver of the plurality of primary station receivers then having a highest congestion parameter;
for the first receiver, to determine an impact level of a transfer for each corresponding secondary station transmitter of the plurality of secondary stations and to select a secondary station transmitter of the plurality of secondary stations then having a highest impact level to form a selected transmitter;
to select a second receiver of the plurality of primary station receivers then having a congestion parameter less than the first threshold and to determine a second congestion parameter for the second receiver in conjunction with the selected transmitter; and
when the second congestion parameter is less than the first threshold, to transfer the selected transmitter to the second receiver.

### Claim 63 (depends on 62)

The apparatus of claim 62, wherein the processor arrangement is further responsive:
to determine whether communication system historical information precludes a potential transfer of the selected transmitter; and
when communication system historical information precludes the potential transfer of the selected transmitter, to select a secondary station transmitter of the plurality of secondary stations then having a next highest impact level to form the selected transmitter.

### Claim 64 (depends on 62)

The apparatus of claim 62, wherein the processor arrangement is further responsive:
to determine whether communication system protocol information precludes a potential transfer of the selected transmitter; and
when communication system protocol information precludes the potential transfer of the selected transmitter, to select a secondary station transmitter of the plurality of secondary stations then having a next highest impact level to form the selected transmitter.

### Claim 65 (depends on 62)

The apparatus of claim 62, wherein the processor arrangement is further responsive, until the congestion parameter of the first receiver has decreased below a hysteresis threshold, to repeatedly:
determine an impact level of a transfer for each corresponding secondary station transmitter of the plurality of secondary stations and to select a secondary station transmitter of the plurality of secondary stations then having a highest impact level to form a selected transmitter;
select a second receiver of the plurality of primary station receivers then having a congestion parameter less than the first threshold and determine a second congestion parameter for the second receiver in conjunction with the selected transmitter; and
when the second congestion parameter is less than the first threshold, transfer the selected transmitter to the second receiver.

### Claim 66 (depends on 65)

The apparatus of claim 65 wherein the first threshold and the hysteresis threshold are predetermined.

### Claim 67 (depends on 65)

The apparatus of claim 65 wherein the first threshold and the hysteresis threshold are adaptive.

### Claim 68 (depends on 62)

The apparatus of claim 62 wherein the congestion parameter is an access latency factor.

### Claim 69 (depends on 40)

The apparatus of claim 40 wherein the processor arrangement is further responsive:
to determine a congestion parameter for each transmitter of a plurality of primary station transmitters to form a plurality of congestion parameters;
when a congestion parameter of the plurality of congestion parameters exceeds a first threshold, to select a first transmitter of the plurality of primary station transmitters then having a highest congestion parameter;
for the first transmitter, to determine an impact level of a transfer for each corresponding secondary station receiver of the plurality of secondary stations and to select a secondary station receiver of the plurality of secondary stations then having a highest impact level to form a selected receiver;
to select a second transmitter of the plurality of primary station transmitters then having a congestion parameter less than the first threshold and to determine a second congestion parameter for the second transmitter in conjunction with the selected receiver; and
when the second congestion parameter is less than first threshold, to transfer the selected receiver to the second transmitter.

### Claim 70 (depends on 69)

The apparatus of claim 69, wherein the processor arrangement is further responsive:
to determine whether communication system historical information precludes a potential transfer of the selected receiver; and
when communication system historical information precludes the potential transfer of the selected receiver, to select a secondary station receiver of the plurality of secondary stations then having a next highest impact level to form the selected receiver.

### Claim 71 (depends on 69)

The apparatus of claim 69, wherein the processor arrangement is further responsive:
to determine whether communication system protocol information precludes a potential transfer of the selected receiver; and
when communication system protocol information precludes the potential transfer of the selected receiver, to select a secondary station receiver of the plurality of secondary stations then having a next highest impact level to form the selected receiver.

### Claim 72 (depends on 69)

The apparatus of claim 69, wherein the processor arrangement is further responsive, until the congestion parameter of the first transmitter has decreased below a hysteresis threshold, to repeatedly:
determine an impact level of a transfer for each corresponding secondary station receiver of the plurality of secondary stations and select the secondary station receiver of the plurality of secondary stations then having a highest impact level to form a selected receiver;
select a second transmitter of the plurality of primary station transmitters then having a congestion parameter less than the first threshold and determine a second congestion parameter for the second transmitter in conjunction with the selected receiver; and
when the second congestion parameter is less than first threshold, transfer the selected receiver to the second transmitter.

### Claim 73 (depends on 72)

The apparatus of claim 72 wherein the first threshold and the hysteresis threshold are predetermined.

### Claim 74 (depends on 72)

The apparatus of claim 72 wherein the first threshold and the hysteresis threshold are adaptive.

### Claim 75 (depends on 69)

The apparatus of claim 69 wherein the congestion parameter further comprises a throughput factor.

### Claim 76 (depends on 40)

The apparatus of claim 40 wherein the apparatus is embodied within a primary station.

### Claim 77 (depends on 40)

The apparatus of claim 40, wherein the processor arrangement further comprises:
a first processor coupled to the channel interface;
a second processor coupled to the channel interface; and
a master controller coupled to the first processor and to the second processor.

### Claim 78

An apparatus for spectrum management in a communication system, the communication system having a communication medium, the communication medium having a plurality of downstream communication channels, the communication medium further having a plurality of upstream communication channels, the communication system further having a plurality of secondary stations coupleable to the communication medium, each secondary station of the plurality of secondary stations having a receiver and a transmitter, the apparatus comprising:
a plurality of channel interfaces coupleable to the communication medium, each channel interface of the plurality of channel interfaces having a transmitter for signal transmission on a downstream communication channel of the plurality of downstream communication channels to form a plurality of primary station transmitters, and each channel interface of the plurality of channel interfaces further having a receiver for signal reception on an upstream communication channel of the plurality of upstream communication channels to form a plurality of primary station receivers;
a plurality of processors coupled to the plurality of channel interfaces; and
a master controller coupled to the plurality of processors, the master controller further having a memory, the master controller responsive through a set of program instructions stored in the memory:
to allocate loading of the plurality of upstream communication channels for an entering secondary station of the plurality of secondary stations based upon a first receive loading factor of a plurality of receive loading factors, the plurality of receive loading factors including a cycle time factor;
to allocate loading of the plurality of downstream communication channels for the entering secondary station based upon a first transmit loading factor of a plurality of transmit loading factors, the plurality of transmit loading factor including a queue depth factor;
to allocate loading of the plurality of upstream communication channels for an active secondary station of the plurality of secondary stations based upon a second receive loading factor of the plurality of receive loading factors and based upon a variation of the plurality of receive loading factors;
to allocate loading of the plurality of downstream communication channels for the active secondary station based upon a second transmit loading factor of the plurality of transmit loading factors and based upon a variation of the plurality of transmit loading factors;
to allocate the plurality of upstream communication channels based upon a first error parameter of a plurality of error parameters and based upon a first channel noise parameter of a plurality of channel noise parameters;
to allocate the plurality of downstream communication channels based upon a second error parameter of the plurality of error parameters and based upon a number of secondary stations of the plurality of secondary stations having the second error parameter;
to allocate loading of the plurality of upstream communication channels based upon a first congestion parameter, the first congestion parameter including an access latency factor; and
to allocate loading of the plurality of downstream communication channels based upon a second congestion parameter, the second congestion parameter including a throughput factor.