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                                                                   Exhibit 10.16

                       ELECTRONIC DATA SYSTEMS CORPORATION
                         STANDARD SUB-SUBLEASE AGREEMENT

      THIS SUB-SUBLEASE AGREEMENT (the "Sub-Sublease") is entered into as of
August 2, 2000, by and between Sub-Sublandlord and Sub-Subtenant hereinafter
named. Upon the terms and conditions hereinafter set forth, Sub-Sublandlord and
Sub-Subtenant agree as follows:

1.    DEFINITIONS AND BASIC PROVISIONS. The following definitions and basic
      provisions shall be used in conjunction with and limited by the reference
      thereto in the provisions of this Sub-Sublease:

      A.    "Sub-Sublandlord":              ELECTRONIC DATA SYSTEMS
                                            CORPORATION, a Delaware corporation

      B.    Address of Sub-Sublandlord:     5400 Legacy Drive, H3-2F-53
                                            Plano, Texas  75024-3105
                                            Attn.: Real Estate Leasing

      C.    "Sub-Subtenant":                SOMERA COMMUNICATIONS, INC.,
                                            a Delaware corporation

      D.    Address of Sub-Subtenant:       5383 Hollister Avenue
                                            Santa Barbara, California 93111

      E.    Sub-Subtenant Federal Tax ID:   75-0521878

      F.    "Sublandlord":                  GRC INTERNATIONAL, INC., a Delaware
                                            corporation

      G.    Address of Sublandlord:         1900 Gallows Road
                                            Vienna, Virginia 22182
                                            Attention: Dick Biller

      H.    "Master Landlord":              SANTA BARBARA CORPORATE CENTER, LLC,
                                            a California limited liability
                                            company, successor-in-interest to
                                            Bermant Development Company

      I.    Address of Master Landlord:     5383 Hollister Avenue
                                            Santa Barbara, CA 93111

      J.    "Sub-Sublease Premises": All space to be occupied by Sub-Subtenant
            as shown on Exhibit "A", attached hereto and made a part of this
            Sub-Sublease, containing approximately 8,913 square feet of net
            rentable area being a portion of the Premises described in the
            Sublease (hereafter defined) being approximately 52,119 rentable
            square feet of space, and located at 5383 Hollister Avenue, Santa
            Barbara, California 93111 (the "Building").

      K.    "Sub-Sublease Term": The period that begins upon the later of (i)
            execution of this Sub-Sublease, or (ii) receipt of consent of Master
            Landlord and Sublandlord to this Sub-Sublease (the "Commencement
            Date") and expiring on March 31, 2004 (the "Expiration Date").

      L.    "Base Rent": Base Rent for the first year shall be $147,789.12 per
            year (subject to base rental abatement described in paragraph 8E
            hereinbelow), payable in the amount of $12,315.76 per month, based
            upon CPI increase which was effective as of April 1, 2000. The
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            annual and monthly Base Rent may be modified after receipt of the
            amount verification from Landlord. This Sub-Sublease is triple net.
            The base rent shall be adjusted annually as provided under Paragraph
            9 of the Master Lease.

      M.    "Sub-Subtenant's Proportionate Share": For the purpose of allocating
            Sub-Subtenant's pro rata share of Operating Expenses, as defined in
            the Master Lease (as hereafter defined) and the Sublease,
            attributable to the Sub-Sublease Premises, Sub-Subtenant's
            Proportionate Share shall be a fraction, the numerator which is the
            total number of the rentable square feet of the Sub-Sublease
            Premises and the denominator which is the total of the rentable
            square feet of the Premises covered by the Sublease, it being agreed
            that Sub-Subtenant's Proportionate Share is 17.10%.

      N.    "Sub-Subtenant's Representatives": Sub-Subtenant's agents,
            representatives and employees.

      O.    "Sub-Sublandlord's Representatives": Sub-Sublandlord's agents,
            representatives and employees.

2.    GRANTING CLAUSE. Sub-Sublandlord, in consideration of the covenants and
      agreements to be performed by Sub-Subtenant and upon the terms and
      conditions hereinafter stated, does hereby lease, demise and let unto
      Sub-Subtenant, and Sub-Subtenant in consideration of the covenants and
      agreements to be performed by Sub-Sublandlord and upon the terms and
      conditions in this Sub-Sublease, does hereby take and lease from
      Sub-Sublandlord, the Sub-Sublease Premises, subject to all laws, statutes,
      codes, rules, regulations and zoning ordinances promulgated by any
      governmental authority having jurisdiction now in affect or adopted in the
      future (collectively, the "Law"), to have and to hold for the Sub-Sublease
      Term (except as the Commencement Date and the Expiration Date may be
      adjusted as herein provided, or unless sooner terminated as provided in
      this Sub-Sublease or the Master Lease).

3.    MASTER LEASE & SUBLEASE. This Sub-Sublease is subject to that certain (a)
      Net Net Net Building Lease (the "Original Lease"), dated April 25, 1995,
      by and between Bermant Development Company, as landlord, and Sublandlord,
      as tenant, as modified by that certain (i) First Amendment to Building
      Lease (the "First Amendment"), dated January 26, 1996, by and between
      Master Landlord and Sublandlord; and (ii) Second Amendment to Building
      Lease (the "Second Amendment"), dated May 9, 1997 (the Original Lease, the
      First Amendment and the Second Amendment are hereinafter collectively the
      "Master Lease", attached hereto as Exhibit "B-1", incorporated herein by
      reference), covering certain premises (the "Premises") more particularly
      described in the Master Lease; and (b) Sublease (the "Sublease"), dated
      March 1, 1999, by and between Sublandlord and Sub-Sublandlord, as
      subtenant, attached hereto as Exhibit "B-2"), incorporated herein by
      reference, covering the Sub-Sublease Premises as the sublease premises.
      This Sub-Sublease is made subject to all applicable covenants,
      restrictions, agreements, terms and conditions of the Master Lease and the
      Sublease, which are incorporated into and made a part of this Sub-Sublease
      as if: i) Sub-Sublandlord were Master Landlord or Sublandlord, as
      appropriate, insofar as Sublandlord has the rights or right by law to act
      as so, and ii) Sub-Subtenant were tenant or Subtenant, as appropriate,
      except as otherwise provided to the contrary herein, excluding paragraphs
      11, 16 and 17 of the Sublease and paragraph 18, 19, 20 and 21 of the
      Master Lease. Sub-Subtenant shall in no case have any rights with respect
      to the Sub-Sublease Premises greater than Sub-Sublandlord's rights as
      tenant under the Master Lease and the Sublease, and Sub-Sublandlord shall
      have no liability to Sub-Subtenant for any matter or thing for which
      Sub-Sublandlord does not have co-extensive liability as tenant under the
      Master Lease and the Sublease. In the event the specific terms of this
      Sub-Sublease are in conflict with the terms of the Master Lease or the
      Sublease, then the specific terms of this Sub-Sublease shall prevail.

4.    MASTER LANDLORD'S AND SUBLANDLORD'S CONSENT. Pursuant to the Master Lease
      and the Sublease, this Sub-Sublease is subject to Master Landlord's and
      Sublandlord's written consent and shall not be valid until Master
      Landlord's and Sublandlord's written
      consent is obtained and delivered to each party. Sub-Sublandlord shall
      diligently pursue obtaining Master Landlord's and Sublandlord's written
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      consent to this Sub-Sublease.

5.    WARRANTY BY SUB-SUBLANDLORD. Sub-Sublandlord warrants and represents to
      Sub-Subtenant, to the knowledge of Sub-Sublandlord, that the Master Lease
      and the Sublease have not been amended or modified, except as provided
      above, that Sub-Sublandlord is not now, and as of the Commencement Date of
      the Sub-Sublease Term hereof, will not be in default or breach of any of
      the provisions of the Master Lease and the Sublease, and that
      Sub-Sublandlord has no knowledge of any claim by Master Landlord or
      Sublandlord that Sub-Sublandlord is in default or breach of any of the
      provisions of the Master Lease or the Sublease.

6.    CONDITION OF THE SUB-SUBLEASE PREMISES. Sub-Subtenant shall accept
      possession of the Sub-Sublease Premises on an "AS IS, WHERE IS" basis, in
      whatever physical condition the same may be, and Sub-Sublandlord makes no
      representations or warranties of any kind or nature, express, implied, or
      otherwise, or any covenants of any kind or nature, with regard to the
      condition of the Sub-Sublease Premises or with respect to the fitness
      thereof for Sub-Subtenant's intended uses or the quality of or manner of
      any services provided or to be provided by Master Landlord or Sublandlord,
      and any such representations, warranties or covenants are hereby expressly
      disclaimed. Without limitation of the foregoing, Sub-Sublandlord shall
      have no obligation to construct or pay for any tenant improvements to the
      Sub-Sublease Premises or make any repairs or modifications thereto for the
      benefit of Sub-Subtenant.

7.    USE.

      A. Sub-Subtenant shall use the Sub-Sublease Premises for the uses set
      forth in the Sublease, unless specifically approved by Sub-Sublandlord,
      Master Landlord and Sublandlord. Sub-Subtenant shall additionally comply
      with the rules and regulations of the Building which Master Landlord or
      Sublandlord may reasonably require or amend from time to time during the
      term of this Sub-Sublease.

      B. Sub-Subtenant shall not do nor permit anything to be done in or about
      the Sub-Sublease Premises nor bring or keep anything therein which will in
      any way increase the existing rate or affect any fire or other insurance
      upon the Building or any of its contents (unless Sub-Subtenant shall pay
      an increased premium as a result of such use or acts), or cause a
      cancellation of any insurance policy covering the Building or any part
      thereof or any of its contents, nor shall Sub-Subtenant sell or permit to
      be kept, used or sold in or about the Sub-Sublease Premises any articles
      which may be prohibited by a standard form policy of fire insurance.

      C. Sub-Subtenant shall not do or permit anything to be done in or about
      the Sub-Sublease Premises which will in any way obstruct or interfere with
      the rights of other tenants or occupants of the Building or injure or
      annoy them or use or allow the Sub-Sublease Premises to be used for any
      unlawful or objectionable purpose, nor shall Sub-Subtenant cause, maintain
      or permit any nuisance in or about the Sub-Sublease Premises.
      Sub-Subtenant shall not commit or suffer to be committed any waste in or
      upon the Sub-Sublease Premises.

      D. Sub-Subtenant shall not knowingly use the Sub-Sublease Premises or
      knowingly permit anything to be done in or about the Sub-Sublease Premises
      which will in any way conflict with the Law. Sub-Subtenant shall at its
      sole cost and expense promptly comply with the Law and with the
      requirements of any board of fire underwriters or other similar body now
      or hereafter constituted relating to or affecting the condition, use or
      occupancy of the Sub-Sublease Premises, excluding structural changes not
      relating to or affecting the condition, use or occupancy of the
      Sub-Sublease Premises, or not related or afforded by Sub-Subtenant's
      improvements or acts. The judgment of any court of competent jurisdiction
      or the admission of Sub-Subtenant, in any action against Sub-Subtenant,
      whether Sub-Sublandlord be a party thereto or not, that Sub-Subtenant has
      violated the Law and with the requirements of any board of fire
      underwriters or other similar body now or hereafter constituted relating
      to or affecting the condition, use or occupancy of the Sub-Sublease
      Premises, excluding structural changes not relating to or affecting the
      condition, use or occupancy of the Sub-Sublease Premises, or not related
      or afforded by Sub-Subtenant's improvements or acts, shall be conclusive
      of the fact as
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      between Sub-Sublandlord and Sub-Subtenant.

8.    RENT.

      A.    Base Rent. Sub-Subtenant agrees to pay equal monthly installments of
            Base Rent to Sub-Sublandlord at the address indicated in Paragraph 1
            above, or such other address as Sub-Sublandlord may from time to
            time notify Sub-Subtenant. Such monthly installments shall be
            payable on or before the first (1st) day of each calendar month
            (without demand, set-off or deduction) commencing as of the
            Commencement Date. Base Rent for any fractional month at the
            beginning or end of the Sub-Sublease Term shall be prorated on
            actual days. Additional rent shall include, without limitation, the
            Operating Expenses, as described below, and any and all other
            charges, costs or expenses otherwise as set forth in the Master
            Lease.

      B.    Operating Expenses. Operating Expenses shall mean any and all costs
            and expenses incurred through the ownership, operation, maintenance
            and insurance of the Building, as more particularly set forth in the
            Master Lease. Sub-Subtenant shall pay Sub-Subtenant's Proportionate
            Share of Operating Expenses of any amounts in excess of the
            Operating Expense Stop in the provided in the Master Lease to
            Sub-Sublandlord.

      C.    Late Charge. In the event that any monthly installment of the Base
            Rent, Operating Expenses and any other additional rent
            (collectively, the "Rent"), or any other payment required to made by
            Sub-Subtenant under this Sub-Sublease is not received within 5 days
            after the due date, Sub-Subtenant agrees to pay a late charge (the
            "Late Charge") in the amount of 3% of the installment of the Rent
            due and unpaid. It is hereby understood and acknowledged that the
            Late Charge shall constitute liquidated damages and such liquidated
            damages shall be solely for the purpose of reimbursing
            Sub-Sublandlord for the additional costs and expenses
            Sub-Sublandlord presently expects to incur in connection with the
            handling and processing of late payments of Rent and any other
            additional rent due and payable under this Sub-Sublease.
            Sub-Sublandlord and Sub-Subtenant agree that in the event of any
            such late payment by Sub-Subtenant, the damages resulting to
            Sub-Sublandlord will be difficult to ascertain precisely, and that
            the Late Charge constitutes a reasonable and good faith estimate by
            the parties of the extent of such damages. If the payment of the
            Rent and any other additional rent continues not to be paid by
            Sub-Subtenant within 30 days after the due date thereof,
            Sub-Subtenant shall additionally pay interest on such unpaid Rent or
            any other additional rent, at the rate of 10% per annum (but in no
            event in excess of the highest interest rate provided by law) which
            interest shall accrue from the due date to the date of payment.

      D.    Non-Waiver of Rights. If Sub-Sublandlord, at any time or times,
            shall accept Rent or any other sum due to it hereunder after the
            same shall become due and payable, such acceptance shall not excuse
            delay upon subsequent occasions, or constitute, or be construed as,
            a waiver of any of Sub-Sublandlord's rights hereunder.

      E.    Base Rental Abatement. Notwithstanding to the contrary contained in
            the Sub-Sublease Agreement, Sub-Sublandlord agrees and acknowledges
            that Sub-Subtenant shall receive an abatement of all Base Rent from
            August 1, 2000 through October 31, 2000 of the Sub-Sublease term.
            Accordingly, Sub-Subtenant's obligation to commence Base Rent
            payments hereunder shall begin on November 1, 2000.

9.    ADDITIONAL SERVICES AND COSTS TO SUB-SUBTENANT. Any additional services
      other than those described in Subparagraph A or in the Sublease or Master
      Lease, services being the types of service which may be usual and
      customary in buildings comparable to the Building in the vicinity of the
      Building (the "Additional Services"), requested by Sub-Subtenant in
      writing to Sub-Sublandlord shall be delivered to Master Landlord or
      Sublandlord, as applicable. Master Landlord or Sublandlord may decide to
      provide the Additional Services in its sole respective discretion,
      provided, however, that the Additional Services shall be billed directly
      to Sub-Subtenant and Sub-Subtenant shall make payments for the Additional
      Services directly to the Master Landlord or Sublandlord. Sub-Sublandlord
      shall not
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      be responsible or liable for Master Landlord's or Sublandlord's failure to
      provide any the Additional Services or the quality of the Additional
      Services. Sub-Subtenant shall pay the Additional Services cost within the
      time period specified by Master Landlord or Sublandlord when an invoice
      for such Additional Service is delivered.

10.   FINANCIAL STATEMENTS. Upon request by Sub-Sublandlord, Sub-Subtenant will
      provide to Sub-Sublandlord financial statements of Sub-Subtenant certified
      by a certified public accountant, reasonably approved by Sub-Sublandlord.
      Sub-Sublandlord may, at Sub-Sublandlord's option request interim certified
      financial statements as may be required by the Master Landlord, the
      Sublandlord or any accounting, financing or legal requirement.

11.   PARKING. In addition to the Sub-Sublease Premises, Sub-Sublandlord hereby
      grants to Sub-Subtenant, subject to the Master Lease and the Sublease and
      so long as this Sub-Sublease remains in effect, four (4) parking spaces
      for every 1,000 rentable square feet of office space.

12.   ASSIGNMENT AND SUBLETTING. Sub-Subtenant shall not assign this
      Sub-Sublease or further sublet all or any part of the Sub-Sublease
      Premises without the prior written consent of Sub-Sublandlord (and the
      consent of Master Landlord and Sublandlord, if such is required under the
      terms of the Master Lease and the Sublease), which shall not be
      unreasonably withheld. Notwithstanding the foregoing, Sub-Sublandlord's
      refusal to consent shall not be deemed to be unreasonable if such proposed
      subtenant or assignee does not have the financial background to perform
      the obligations under the Master Lease, intends to utilize the
      Sub-Sublease Premises for purposes other than allowed under the Master
      Lease and the Sublease or Master Landlord or Sublandlord fail to consent
      to such assignment or sublease. Sub-Subtenant shall not be in default
      under the terms and conditions of this Sub-Sublease or the Master Lease at
      the time of any request for consent or through the period of time prior to
      the consent is granted by Master Landlord and Sublandlord. Any request by
      Sub-Subtenant for Sub-Sublandlord's consent to a specific assignment or
      Sub-Sublease shall include a) the name of the proposed assignee,
      sublessee, or occupant, b) the nature of the proposed assignee's,
      sublessee's or occupant's business to be carried on in the Sub-Sublease
      Premises, c) a copy of the proposed assignment or Sub-Sublease, and d)
      such financial information and such other information as Sub-Sublandlord
      may reasonably request concerning the proposed assignee, sublessee or
      occupant or its business. Any assignment or Sub-Sublease approved by
      Sub-Sublandlord, Sublandlord and Master Landlord shall be subject to the
      Master Lease, the Sublease and this Sub-Sublease. Sub-Subtenant shall pay
      to Sub-Sublandlord all reasonable costs incurred related to the review of
      the subletting or assignment documents and costs incurred in obtaining
      Master Landlord's and Sublandlord's consents. Additionally, for purposes
      of this Sub-Sublease, the following transactions relating to Sub-Subtenant
      shall be deemed an assignment of this Sub-Sublease and shall give rise to
      the requirement of approval or consent by Sub-Sublandlord, and may result
      in the right to terminate or alter this Sub-Sublease, based upon the
      above: any merger (including, without limitation, a reincorporation
      merger), consolidation, reorganization, stock exchange, one or more sales
      or transfers of stock, by operation of law or otherwise, or creation of
      new stock, by which an aggregate of more than 50% of Sub-Subtenant's stock
      shall be vested in a party or parties who are nonstockholders as of the
      date hereof; and the sale or transfer of substantially all of the assets
      or other similar or related transaction in which Sub-Subtenant is the
      surviving entity or, if Sub-Subtenant is not the surviving entity, the
      surviving entity which continues to conduct the business conducted by
      Sub-Subtenant prior to consummation of the transaction. The foregoing
      related to sale or transfer of stock shall not apply if Sub-Subtenant's
      stock is listed on a recognized security exchange. For the purpose of this
      paragraph, stock ownership shall be determined in accordance with the
      principles set forth in Section 544 of the Internal Revenue Code of 1954,
      as amended. If the Rent being charged or any other concessions granted
      under any assignment or Sub-Sublease exceeds the Rent charged under this
      Sub-Sublease, any excess amounts shall be shared as provided in the Master
      Lease and/or the Sublease. If the Master Lease or Sublease does not have a
      provision for sharing excess rent amounts, any excess amounts shall be
      shared equally between Sub-Sublandlord and Sub-Subtenant.

13.   SUB-SUBTENANT'S INSURANCE. Sub-Subtenant shall, at its sole cost and
      expense, obtain and maintain commercial general liability insurance,
      including blanket contractual liability coverage, with
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      limits of not less than $2,000,000.00 combined single limit for personal
      injury and property damage; comprehensive automobile liability insurance
      covering all owned, non-owned and hired vehicles with limits of not less
      than $1,000,000.00 combined single limit for personal injury and property
      damage; and statutory workers compensation (in amounts required by law)
      and reasonable employers liability, and naming Sub-Sublandlord,
      Sublandlord and Master Landlord as additional insureds, as their
      respective interests may appear. The insurance policy shall be written by
      good and solvent insurance companies able to do business in California,
      and satisfactory to Sub-Sublandlord, Sublandlord and Master Landlord, if
      required by the Master Lease. On or before the Commencement Date of the
      Sub-Sublease Term, and within 30 days prior to the expiration of any such
      policy, Sub-Subtenant shall deliver to Sub-Sublandlord a duplicate policy
      or certificate of insurance evidencing such coverages. Such insurance
      policies shall provide for no cancellation or material alteration without
      30 days' prior written notice to Sub-Sublandlord.

14.   INDEMNIFICATION

      A. Sub-Subtenant's Indemnification. Sub-Subtenant shall indemnify, defend
      and hold Sub-Sublandlord and Sub-Sublandlord's Representatives harmless
      from any and all liabilities, responsibilities or claims to Sub-Subtenant,
      or any person claiming by, through or under Sub-Subtenant, arising from
      (a) Sub-Subtenant's use and occupancy of the Premises; or (b) the conduct
      of Sub-Subtenant's business; or (c) from any activity, work or thing done,
      permitted or suffered by Sub-Subtenant in or about the Premises, the
      Building or the Property, or (d) any breach or default in the performance
      of any obligation to be performed by Sub-Subtenant under the terms of the
      Lease or arising from any act, neglect, fault or omission or Sub-Subtenant
      or Sub-Subtenant's Representatives, and from and against all costs,
      reasonable attorneys' fees, expenses and liabilities incurred in or about
      such claim or any action or proceeding brought, excluding consequential
      and punitive damages. In case any action or proceeding shall be brought
      against Sub-Sublandlord by reason or any such claim Sub-Subtenant, upon
      receipt of notice from Sub-Sublandlord shall defend the same at
      Sub-Subtenant's expense.

            B.    Sub-Sublandlord's Indemnification. Sub-Sublandlord shall
                  indemnify, defend and hold Sub-Subtenant and Sub-Subtenant's
                  Representatives harmless from any and all liabilities,
                  responsibilities or claims to Sub-Sublandlord, or any person
                  claiming by, through or under Sub-Sublandlord, arising from
                  (a) the ownership, operation, maintenance, repair and
                  management of the Building and the Property; or (b) the
                  conduct of Sub-Sublandlord's business; or (c) from any
                  activity, work or thing done, permitted or suffered by
                  Sub-Sublandlord in or about the Premises, the Building or the
                  Property, or (d) any breach or default in the performance of
                  any obligation to be performed by Sub-Sublandlord under the
                  terms of this Lease or arising from any act, neglect, fault or
                  omission or Sub-Sublandlord or Sub-Sublandlord's
                  Representatives, and from and against all costs, reasonable
                  attorneys' fees, expenses and liabilities incurred in or about
                  such claim or any action or proceeding brought, excluding
                  consequential and punitive damages. In case any action or
                  proceeding shall be brought against Sub-Subtenant by reason or
                  any such claim, Sub-Sublandlord, upon receipt of notice from
                  Sub-Subtenant shall defend the same at Sub-Sublandlord's
                  expense.

15.   SUB-SUBLANDLORD'S OBLIGATIONS. Sub-Sublandlord shall have no obligation to
      perform any of Master Landlord's obligations under the Master Lease, or,
      Sublandlord's obligations under the Sublease, including, without
      limitation, (i) providing any of the services that Master Landlord or
      Sublandlord has agreed to provide pursuant to the Master Lease or Sublease
      (or required by law), or (ii) furnishing the electricity to the
      Sub-Sublease Premises that Master Landlord has agreed to furnish pursuant
      to the Master Lease (or required by law), or (iii) making any of the
      repairs or restorations that Master Landlord or Sublandlord has agreed to
      make pursuant to the Master Lease or Sublease (or required by law), or iv)
      complying with any laws or requirements of any governmental authorities,
      unless Sub-Sublandlord occupies a portion of the Original Premises which
      would affect the Sub-Sublease Premises, or v) take any other action that
      Master Landlord or Sublandlord has agreed to provide, furnish, make,
      comply with, or take, or cause to be provided, furnished, made, complied
      with or taken under the Master Lease or the Sublease. Sub-Subtenant shall
      have no rights against Sub-
<PAGE>

      Sublandlord arising out of the Master Landlord's or Sublandlord's failure
      to perform any of its obligations under the Master Lease or Sublease, as
      applicable. Sub-Subtenant shall have the right to institute an action
      under the provisions of the Master Lease to the extent such action relates
      to the Sub-Sublease Premises, provided Sub-Subtenant gives Sub-Sublandlord
      at least 30 days prior written notice and Sub-Sublandlord has failed to
      take action within that time. Notwithstanding the foregoing, if an action
      or cure cannot be completed within 30 days after receipt, however, such
      action or cure is commenced within 30 days after receipt of notice, and is
      diligently being pursued, Sub-Subtenant shall have no right to pursue
      Master Landlord or Sub-Sublandlord. If Sub-Subtenant subsequently pursues
      such action, Sub-Subtenant agrees to reimburse Sub-Sublandlord for its
      proportionate share of any costs incurred by Sub-Sublandlord in connection
      with Sub-Subtenant instituting any such action. Sub-Sublandlord shall give
      reasonable assistance to Sub-Subtenant in enforcing the terms of the
      Master Lease or the Sublease, and will execute all documents reasonably
      necessary to enable Sub-Subtenant to pursue Master Landlord or Sublandlord
      in its failure to perform any of its obligations under the Master Lease or
      the Sublease.

16.   CONSENTS. Wherever consent by Master Landlord is required under the Master
      Lease and Sublandlord is required under the Sublease, Sub-Sublandlord's
      consent shall also be required. Except as specifically set forth herein,
      Sub-Sublandlord agrees that whenever its consent or approval is required
      hereunder, or where something must be done to Sub-Sublandlord's
      satisfaction, it shall not unreasonably withhold or delay such consent or
      approval; provided, however, that whenever the consent or approval of
      Master Landlord, Sublandlord, the landlord under a superior lease, or the
      mortgagee under a mortgage shall withhold its consent or approval for any
      reason whatsoever, Sub-Sublandlord shall not be deemed to be acting
      unreasonably if it shall also withhold its consent or approval.

17.   LIMITATION OF LIABILITY OF SUB-SUBLANDLORD. In the event Sub-Sublandlord
      shall be liable to Sub-Subtenant for any matter relating to or arising in
      connection with this Sub-Sublease, whether based upon an action or claim
      in contract, equity, negligence, intended conduct, tort or otherwise, the
      amount of damages recoverable against Sub-Sublandlord for all events, acts
      or omissions shall in no event include, nor will Sub-Sublandlord be liable
      for, any amounts for loss of profits, income or savings or indirect,
      consequential, speculative or punitive damages of any party, including
      third parties. Further, no cause of action may be asserted against
      Sub-Sublandlord later than the earlier of a) the applicable statute of
      limitations for notice of such cause of action, or b) 2 years following
      the date after the date on which Sub-Subtenant becomes aware of the matter
      which gives to the cause of action shall have accrued. Sub-Sublandlord and
      Sub-Subtenant expressly acknowledge that the limitations contained in this
      Paragraph 17 have been the subject of active and complete negotiation
      between the parties and represent the parties' agreement.

18.   NOTICES. All notices and demands which may or are to be required or
      permitted to be given by either party to the other hereunder shall be in
      writing and shall be deemed given when actually received, or if refused,
      when delivery was attempted. All notices and demands by Sub-Sublandlord to
      Sub-Subtenant shall be sent by c) Federal Express or some other bonded,
      national, professional overnight courier; d) United States Mail, certified
      or registered mail, return receipt requested, postpaid; or (c) sent by
      telecommunication ("Fax") during normal business hours in which case it
      shall be deemed delivered on the day sent, provided an original is
      received by the addressee after being sent by a nationally recognized
      overnight courier within 1 business day of the Fax, addressed to
      Sub-Subtenant at the address indicated in Paragraph 1 E above or to such
      other person or place as Sub-Subtenant may from time to time designate in
      a notice to Sub-Sublandlord. All notices and demands by Sub-Subtenant to
      Sub-Sublandlord shall be sent in the same manner as set forth above to the
      address set forth in Paragraph 1 B above or to such other person or place
      as Sub-Sublandlord may from time to time designate in a notice to
      Sub-Subtenant.

19.   OPTIONS PERSONAL. Any option (the "Option") set forth in the Master Lease
      or the Sublease shall be personal to Sublandlord, as tenant, under the
      Master Lease and to Sub-Sublandlord, as subtenant, under the Sublease, and
      may not be exercised or assigned, voluntarily or involuntarily, by, or to,
      any person or entity other than Sublandlord, as tenant. The Option is not
      assignable separate and apart
<PAGE>

      from the Master Lease or the Sublease. Sublandlord's option to cancel
      under the Sublease has expired.

      IN WITNESS WHEREOF, this Sub-Sublease is executed as of the date first
written above.

SUB-SUBLANDLORD:                         SUB-SUBTENANT:

ELECTRONIC DATA SYSTEMS CORPORATION      SOMERA COMMUNICATIONS, INC.


By:    /s/ Daniel F. Busch               By:        /s/ Jeffrey G. Miller
   ---------------------------------        ------------------------------------
           Daniel F. Busch               Printed Name:  Jeffrey G. Miller
                                                      --------------------------
Title:     Director of Real Estate       Title:  Exec. VP of Sales & Marketing
                                               ---------------------------------

Dated:            8/3/00                 Dated:            8/2/00
      ------------------------------           ---------------------------------