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[LETTERHEAD]

                         ADAPTIVE BROADBAND CORPORATION

                               SEVERANCE AGREEMENT


THIS SEVERANCE AGREEMENT is entered into as of July 2, 1999 (the "Effective
Date"), between ADAPTIVE BROADBAND CORPORATION, a Delaware corporation ("ADAP")
and Kenneth Wees (the "Employee").

                                     RECITAL

The Employee serves as ADAP's Vice President, General Counsel. ADAP and the
Employee desire to set forth the terms of the Employee's severance compensation
if the Employee's employment is ended as a result of a Change in Control. If a
Change in Control occurs, the Employee and other key employees may be more
vulnerable to dismissal or other negative consequences without regard to the
quality of their past or prospective service. The Board of Directors (the
"Board") believes that it is in the best interest of ADAP and its stockholders
to ensure fair treatment to ADAP's key executives and to reduce any adverse
effects upon their performance that may be caused by the perceived risks of a
merger, acquisition or other major structural change.

The parties agree as follows:

1.     DEFINITIONS. For purposes of this Agreement, the following terms will
       have the meanings set forth below.

              1.1    A "CHANGE IN CONTROL" will occur if (a) any Person (as
                     defined in Section 2(a)(2) of the Securities Act of
                     1933, as amended) other than ADAP, is or becomes the
                     beneficial owner, directly or indirectly (including by
                     holding securities which are exercisable for or
                     convertible into shares of capital stock of ADAP), of 30
                     % or more of the combined voting power of the
                     outstanding shares of capital stock of ADAP entitled to
                     vote generally in the election of directors ; or, (b) a
                     Transaction is consummated; or, (c) Continuing Directors
                     cease to constitute at least a majority of the Board:
                     or, (d) a majority of the ADAP's Outside Directors
                     determine that a Change in Control has occurred.

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              1.2    "CONTINUING DIRECTORS" shall mean the directors of ADAP
                     in office on January 1, 1999 and any successor to any
                     such director whose nomination or selection was approved
                     by a majority of the directors in office at the time of
                     the director's nomination or selection and who is not an
                     "affiliate" or "associate" (as defined in Rule 12b-2
                     under the Securities Exchange Act of 1934, as amended)
                     of any person who is the beneficial owner, directly or
                     indirectly (including by holding securities which are
                     exercisable for or convertible into shares of capital
                     stock of ADAP), of 10% or more of the combined voting
                     power of the outstanding shares of capital stock of ADAP
                     entitled to vote generally in the election of directors.

              1.3    "DISABILITY" means that the Employee has met the
                     qualifications for ADAP's long-term disability benefit.

              1.4    "GOOD REASON" includes any of the following:

                     (a)    the assignment to the Employee of duties
                            inconsistent with, or a substantial alteration in
                            the nature or status of, the Employee's
                            responsibilities immediately before a Change in
                            Control;

                     (b)    a reduction in the Employee's salary or other
                            benefits as in effect on the date of a Change in
                            Control;

                     (c)    the Employee's relocation to a work site requiring
                            an increase in one-way commute from Employee's
                            residence of more than thirty-five (35) miles; or

                     (d)    a breach by ADAP of this Agreement if the breach has
                            not been cured within 30 days after written notice
                            by the Employee to ADAP setting forth with
                            specificity the nature of the breach.

              1.5    "OUTSIDE DIRECTOR" is a member of ADAP's Board of Directors
                     who is not, and who during the past six months was not, an
                     employee or officer of ADAP.

              1.6    "TERMINATION FOR CAUSE" is termination of the Employee's
                     employment as a result of (a) the Employee's willful
                     misconduct or the Employee's dishonesty towards, fraud
                     upon, crime against or

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                     deliberate or attempted injury or bad faith action with
                     respect to ADAP; or (b) the Employee's conviction for a
                     felony (whether in connection with ADAP's affairs or
                     otherwise).

              1.7   "TERMINATION UPON A CHANGE IN CONTROL" is (a) termination by
                    the Employee of Employee's employment for Good Reason within
                    one year after the occurrence of a Change in Control; or (b)
                    declination by the Employee of an offer of employment from
                    ADAP, or ADAP's successor, for Good Reason at the time of a
                    Change in Control if the Employee would not have been
                    permitted to remain in Employee's existing position
                    following such declination; or (c) termination by ADAP, or
                    ADAP's successor, of the Employee's employment within one
                    year after the occurrence of a Change in Control other than
                    a Termination for Cause or a termination resulting from the
                    Employee's death or Disability. The one-year period provided
                    for herein shall be six months in the event that a Change in
                    Control arises out of a Transaction defined in Section 1.8
                    (c) hereof.

              1.8   "TRANSACTION" is (a) a consolidation or merger of ADAP if
                    the shareholders of ADAP immediately before the merger or
                    consolidation do not immediately after the merger or
                    consolidation own equity securities of the surviving or
                    acquiring corporation or a parent party possessing 50% or
                    more of the voting power of the surviving or acquiring
                    corporation or parent party; (b) a sale, lease, exchange or
                    other transfer (in one transaction or a series of related
                    transactions) of 50% or more of the assets of ADAP; or (c)
                    the sale or other disposition of business units within any
                    12-month period that contributed for that 12-month period
                    more than 45% of ADAP's revenues. The Transaction
                    requirements defined in parts (b) and (c) above shall
                    specifically exclude the sale of the Information Systems
                    division and its associated assets, and the designated
                    percentage thresholds for assets and revenues stated herein
                    (50% and 45%, respectively) shall be calculated without
                    including this division's assets or revenues in the base.

2.     TERM. If no Change in Control has occurred, this Agreement will expire on
       December 31, 2000. If a Change in Control occurs prior to December 31,
       2000, this Agreement will continue in effect, and will not terminate,
       until either the Employee has received the severance compensation
       provided for below or has ceased to be eligible for such compensation by
       reason of there not having been a Termination Upon a Change in Control.

3.     TERMINATION UPON A CHANGE IN CONTROL. If a Termination Upon a Change in
       Control

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       occurs, the Employee will immediately be paid all (a) accrued salary,
       (b) bonus compensation equal to the higher of (i) the annual EIP bonus
       based on ADAP's operating plan as approved by the Board during the
       first quarter of the fiscal year during which the Change in Control
       occurs, provided that the EVA growth for such fiscal year as of the
       most recently completed fiscal quarter is equal to that specified in
       the operating plan for such period, or (ii) the annual bonus or other
       equivalent incentive compensation payment established for the Employee
       by ADAP's successor and based on the operating plan of ADAP's
       successor at the beginning of the bonus's performance period during
       which Employee's termination occurs, (c) vested deferred compensation
       (other than pension plan or profit sharing plan benefits, which will
       be paid in accordance with the applicable plan), unless the Employee
       is eligible for a delayed payout as authorized by the plan, (d)
       benefits then due under any plans of ADAP or ADAP's successor in which
       the Employee is a participant, (e) accrued Personal Time Off pay or
       vacation pay and (f) reimbursements for any appropriate business
       expenses incurred by the Employee in connection with his duties, all
       to the date of termination ("Accrued Compensation"). Repayment of any
       existing company loans shall be extended if necessary to delay
       repayment until the beginning of regular employment during the period
       of severance compensation provided for in Section 4. The Employee will
       also be entitled to the severance compensation described in Section 4.

4.     SEVERANCE COMPENSATION. If a Termination Upon a Change in Control
       occurs, ADAP shall pay monthly severance compensation to the Employee
       for a period  ending 24 months after termination, or ending 12 months
       after termination if the Termination Upon a Change in Control (i) is
       initiated by the Employee as specified in Sections 1.7 (a) or 1.7 (b)
       and (ii) is by reason of a Transaction defined in Section 1.8 (c), in
       an aggregate amount determined by adding (a) the Employee's monthly
       base salary at the time of termination and (b) an amount equal to the
       monthly `Perk Pot' benefit to which the Employee was entitled as an
       officer of ADAP at the time of the Change in Control, and (c) the
       amount of $2400.00 in lieu of other employee benefits (including
       health benefits) the Employee was receiving from ADAP at the time of
       the Change in Control. If the Employee begins regular employment prior
       to the expiration of the aforesaid 24 month period, or 12 month period
       if the Termination Upon a Change in Control (i) is initiated by the
       Employee as specified in Sections 1.7 (a) or 1.7 (b) and (ii) is by
       reason of a Transaction defined in Section 1.8 (c), then the severance
       compensation provided for in this Section 4 shall end as of the later
       of (i) the date of such regular employment or (ii) the date which is
       one-half the number of months past he beginning of severance
       compensation provided for in this Section 4. Employee agrees to
       promptly notify ADAP of any such regular employment and to reimburse
       ADAP for any payments made by ADAP hereunder that cover any period
       during which the Employee was a regular employee.

5.     ACCELERATION OF OPTIONS. If a Termination Upon a Change in Control
       occurs, all stock options held by the Employee immediately before the
       termination will become fully vested and the stock options will be
       exercisable for the periods specified with respect to termination of
       employment in the plans covering the options.

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6.     OTHER BENEFITS. Neither this Agreement nor the severance compensation
       that it provides for will reduce any amounts otherwise payable, or in any
       way diminish the Employee's rights as an employee of ADAP, whether
       existing now or hereafter, under any benefit, incentive, retirement,
       stock option, stock bonus or stock purchase plan or under any employment
       agreement or other plan or arrangement, provided, however, that the
       rights granted to the Employee and the obligations assumed by ADAP under
       this Agreement will be in lieu of, and not in addition to, any severance
       or other termination payments to which the Employee may be entitled under
       any employment agreement or other plan or arrangement that the Employee
       may now or hereafter have with ADAP.

7.     EMPLOYMENT STATUS. This Agreement does not constitute a contract of
       employment. It does not impose on ADAP any obligation to retain the
       Employee as an employee, to change the status of the Employee's
       employment or to change ADAP's policies regarding termination of
       employment.

8.     MISCELLANEOUS.

       a.     SEVERABILITY. If a court or other body of competent jurisdiction
              determines that any provision of this Agreement is invalid or
              unenforceable, that provision will be adjusted rather than voided,
              if possible, so that it is enforceable to the maximum extent
              possible, and all other provisions of the Agreement will be deemed
              valid and enforceable to the fullest extent possible.

       b.     WITHHOLDING. Compensation and benefits to the Employee under this
              Agreement will be reduced by all federal, state, local and other
              withholdings or similar taxes as required by applicable law.

       c.     ARBITRATION. The parties will submit all controversies, claims and
              matters of difference in any way related to this Agreement, its
              performance or breach, to arbitration in San Francisco,
              California, according to the rules and practices of the American
              Arbitration Association from time to time in effect. Any awards in
              such arbitration shall be final and binding on all parties. The
              arbitrators shall allocate the costs of the arbitration in such
              manner as they deem equitable. The arbitrators may require the
              reimbursement of all or a portion of the reasonable legal fees
              incurred by the prevailing party in the arbitration proceeding and
              any legal proceedings which are taken to enforce the arbitral
              award.

       d.     ENTIRE AGREEMENT: MODIFICATIONS. (i) This Agreement is the entire
              agreement between the parties with respect to the matters covered
              hereby, and may be amended, modified, superseded or canceled, or
              its terms waived, only by a written instrument executed by each
              party or, in the case of a waiver, by the

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              party waiving compliance. (ii) Failure of a party at any time
              to require performance of any provision of this Agreement will
              not affect the right at a later time to enforce the same. (iii)
              No waiver of a breach of this Agreement, whether by conduct or
              otherwise, in any one or more instances will be construed as a
              further or continuing waiver of the breach or of any other term
              of this Agreement. (iv) This Agreement shall inure to the
              benefit of and be binding upon the successors and assigns of
              the parties hereto.

       e.     APPLICABLE LAW. This Agreement will be construed under and
              governed by the laws of the State of California without regard or
              reference to the rules of conflicts of law that would require the
              application of the laws of any other jurisdiction.

9.     Prior Severance Agreement. The Employee and ADAP (named "California
       Microwave, Inc." prior to April 29, 1999) acknowledge their prior
       severance agreement dated May 26, 1998. The Employee and ADAP hereby
       terminate such prior severance agreement as of the day immediately prior
       to the Effective Date of this Agreement, and neither the Employee nor
       ADAP shall have any rights or obligations thereunder.


IN WITNESS WHEREOF, the parties have executed this Agreement as of the day and
year first above written.

ADAPTIVE BROADBAND CORPORATION


  /s/  Frederick D. Lawrence
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Frederick D. Lawrence                      Kenneth Wees
Chairman and Chief Executive Officer       Vice President, General Counsel